Classic dishes don't have to be baked from scratch, Rosie Reynolds believes. In fact, professional chefs have always used shortcuts to make great food, and it's time everyone else did too.

"Home cooks have not always been allowed the same privilege and are often made to feel guilty about using certain tricks and ingredients," the London-based food stylist and recipe writer writes in her new cookbook, The Shortcut Cook.

The collection includes more than 60 favourite recipes, from shepherd's pie to sticky pudding, with clever shortcuts and time-saving tricks that don't sacrifice flavour.

"It'll give you permission to use your microwave, to use store-bought bits 'n' bobs and to use food from the freezer," Reynolds says.

"It will also teach you some techniques, methods and a few unusual ingredient combos to help you achieve good-looking, great-tasting food."

Here are five recipes to make cooking delicious food at home a whole lot easier.

One-dish lasagne

Nowadays, I make my lasagne from start to finish in the same large shallow casserole dish, as I want to keep all of the flavour in one place. Adding a drizzle of cream to the ragu thickens and makes the sauce deliciously rich without lengthy cook times. Gone is the (often lumpy) bechamel sauce, replaced with a mix of creamy ricotta, gooey mozzarella and parmesan. And to speed the whole thing up, I soak the dried lasagne sheets in warm water before layering. You'll be so chuffed with the lack of washing up, it's sure to become a regular dinner-time fix.

INGREDIENTS

• 1 tablespoon olive oil, plus extra for drizzling
• 1 onion, chopped
• 500g 20 per cent fat minced beef
• 4 garlic cloves, grated
• 700g passata with basil
• 1 teaspoon dried oregano
• 1 beef or chicken stock cube
• 200ml (scant 1 cup) hot water
• 100ml (scant ½ cup) double cream, plus extra 2 tablespoons
• handful of fresh basil leaves (optional)
• 8-12 lasagne sheets (depending on size)
• 250g ricotta, drained
• 250g mozzarella, drained and cut into small cubes
• 75g parmesan, grated sea salt and freshly ground black pepper

METHOD

1. Heat the olive oil in a large, shallow, flameproof casserole dish over a medium-high heat. Fry the onion for 2 minutes until starting to soften, then add the minced beef. Increase the heat to high and fry for 3 minutes, stirring frequently until the beef has browned all over. Throw in the garlic and fry for 1 minute.
2. Pour the passata into the dish with the dried oregano and crumble in the stock cube. Fill the passata jar with the hot water, swirl it around, then add to the sauce. Bring the mixture to the boil, then add the 100ml cream. Tear half of the basil leaves (if using) and add to the sauce with plenty of seasoning. Cook for 5 minutes until the sauce is starting to thicken and look rich in colour, then remove from the heat.
3. Preheat the oven to 180C fan-forced (200C conventional). Fill a large bowl with hand-hot water and a drizzle of oil, then slide in the pasta sheets and leave to soak for a few minutes.
4. Use a ladle to scoop two-thirds of the ragu out into a heatproof bowl. Spread out the remaining third over the base of the casserole dish. In a separate bowl, loosen the ricotta with the extra 2 tablespoons cream and 1 tablespoon of the pasta soaking water.
5. Lift out and drain enough pasta sheets to cover the surface of the ragu in the casserole dish, laying them gently on top. Spread a third of the ricotta mixture over the pasta, then scatter over a third of the mozzarella and a third of the parmesan. Add another layer of ragu and repeat until all of the ingredients have been used, finishing with a cheese layer.
6. Cover the dish with kitchen foil and bake in the hot oven for 15 minutes. Remove the foil and return the dish to the oven for a further 15 minutes, or until the pasta is tender and the lasagne bubbling.

Make ahead Freeze this, unbaked, for up to 1 month, and defrost overnight before cooking. The meat sauce will keep well in the refrigerator for 1-2 days.

The shortcut Just 1 pan and no bechamel prep – you're at least 3 hours ahead with your lack of authenticity.

Serves 4, with leftovers

A really good shepherd's pie

I use a very Asian trio of flavours in my shepherd's pie, which you might not think is a natural fit in a quintessentially British dish, but trust me – it really works. You will have the ingredients in your pantry, and their inherent characteristics can transport even the most traditional British dish to an umami fest. The miso, soy and fish sauce round out the flavours of the dish without overpowering it, making a good dish even more delicious.

Shepherd's pie calls for minced lamb, but this can be interchanged with minced beef. Lamb is naturally fattier, so if you're using beef, make sure you look out for a mince with 20 per cent fat. Remember – fat is flavour! I have to admit, I don't like making mashed potato, so I use store-bought, jazzed up with extra butter and milk. I know many people don't share my disdain for mashing, in which case make your own.

If you don't have a casserole dish that can go in the oven, then transfer the meat to a baking dish before topping it with potato. Just cool the meat first, so the mash doesn't sink.

INGREDIENTS

• 1 tablespoon olive oil
• 1 onion, chopped
• 1 leek, halved lengthways and chopped
• 1 celery stalk, chopped
• 3 large carrots, diced
• 2 garlic cloves, grated
• 2 tablespoons thyme leaves or 1 teaspoon dried thyme
• 500g minced lamb or beef
• 1 tablespoon plain flour
• 2 fresh or dried bay leaves
• 1½ tablespoons miso
• 1 tablespoon dark soy sauce
• 1 tablespoon tomato paste
• 2 teaspoons fish sauce
• 200ml (scant 1 cup) water
• 900g mashed potatoes (about 6 large potatoes, boiled and mashed)
• 3 tablespoons whole (full-fat) milk
• 1 tablespoon butter
• 100g strong cheddar, grated

METHOD

1. Heat the oil in a large, shallow, flameproof casserole dish set over a medium heat. Fry the onion, leek, celery and carrots for 10 minutes, stirring frequently, until starting to soften. Add the garlic and thyme, then push the vegetables to the edge of the pan. Increase the heat, add the meat and fry for 5 minutes until brown, breaking it up with a wooden spoon as you go. Sprinkle over the flour and cook for a further minute.
2. Throw the bay leaves into the pan, then stir in the miso, soy sauce, tomato puree, fish sauce and water. Bring to a simmer and cook for 20 minutes.
3. Remove the dish from the heat and allow to cool for about 10 minutes. (You can cool completely and freeze the meat mixture at this point.)
4. Preheat the oven to 180C fan-forced (200C conventional).
5. In a separate saucepan, heat the mashed potato with the milk and butter, stirring until smooth and warmed through.
6. Top the cooled meat mixture with the mashed potato and rough up the surface with a fork. Scatter over the cheese and cook in the oven for 20 minutes, or until golden and bubbling.

Make ahead Once assembled, this will sit happily in the refrigerator for 2 days before cooking, and the meat sauce will keep in the freezer for up to 2 months.

The shortcut A savoury flavour bomb is achieved in minutes with the trio of umami-rich ingredients – trust me, it will taste as though you've slow-cooked it for hours.

Serves 4

My eggplant parmigiana

If there is anything better than an eggplant parmigiana, it is an easy eggplant parmigiana. Remove the slicing, salting, dipping in egg, frying, dirty plates, dirty fingers, dirty shirt fronts ... it doesn't get any easier than my version.

I use a combination of oil and butter – the butter cooks and adds a delicious creamy, nutty flavour to the final sauce that surrounds your slow-cooked, falling apart, unctuous eggplants. It's topped with parmesan and a few breadcrumbs, I love how some of the cheesy breadcrumbs become soft as they soak up the delicious tomato sauce, while others crisp up. The textural contrasts are just the ticket and hit all the high notes that a traditionally made parmigiana would.

I serve this dish with a big green salad, but if you're not in the mood for salad, try the cooked eggplant stuffed in a hollowed-out crusty baguette – it's the stuff of dreams.

INGREDIENTS

• 4 medium eggplants
• olive oil, for brushing and cooking
• large knob of butter, softened
• 2 x 400g tins chopped tomatoes
• 2 garlic cloves, grated
• 1 teaspoon dried oregano
• 2 x 125g balls mozzarella, cubed
• 30g parmesan, finely grated
• large handful of fresh breadcrumbs
• large handful of basil leaves (optional)
• sea salt and freshly ground black pepper

METHOD

1. Preheat the oven to 180C fan-forced (200C conventional).
2. Make deep slits, 1cm (apart, across each of the eggplants, making sure you don't cut all of the way through. Use a pastry brush to coat the inside of the cuts with oil. Dot the butter over each of the eggplants and season inside and out.
3. Mix together the tomatoes, garlic, oregano and some seasoning – I usually do this in the tomato tins. Pour the tomato mixture into a 20 x 30cm baking dish and sit the eggplants on top. Cover with kitchen foil and cook in the oven for 50 minutes, or until the eggplants are starting to get really soft.
4. Remove the dish from the oven and remove the foil. Use the back of a spoon to open up the eggplant cuts and stuff with cubes of mozzarella and some of the tomato sauce. Sprinkle over the parmesan and breadcrumbs, then return the dish to the oven and cook uncovered for a final 10 minutes, or until the breadcrumbs are golden.
5. Leave to stand for 5 minutes, then scatter with basil (if using) before serving.

Make ahead Prep the whole dish in advance and reheat in a hot oven until piping hot.

The shortcut All the textural expectations of a parmigiana, none of factory line-style crumbing. No salting, no dipping in egg, no frying in oil. One pan, no-hassle cooking.

Serves 4

Easiest fish pie

Fish pie is the epitome of comfort food. What it lacks in looks, it makes up for in taste and texture. I use a fish pie mix containing salmon, cod and smoked haddock. It's easy enough to find and the supermarket has very kindly done all the dirty work for you by chopping it up. I don't bother with a bechamel sauce, opting instead for a mix of double cream and fish stock. The little bit of cornflour used to dust the fish thickens the sauce as the pie cooks, resulting in a rich, velvety, savoury sauce without the hassle of making a bechamel.

Adding a handful of crushed croutons at the end of cooking provides a delicious crunch that works brilliantly with the soft mashed-potato topping. As you'll probably know by now, I don't like mashing potatoes, so I use pre-made shop-bought mash, but you can mash your own, if you like.

INGREDIENTS

• 2 tablespoons butter
• 6 spring onions, chopped
• 2 x 400g packets fish pie mix
• 2 teaspoons cornflour
• 1 tablespoon Dijon mustard
• 300ml (1¼ cups) double cream
• 200ml (scant 1 cup) fish stock
• 150g cooked prawns
• 150g (generous 1 cup) frozen peas, defrosted (optional)
• bunch of flat-leaf parsley, roughly chopped
• 800g (3½ cups) pre-cooked mashed potato (if mashing your own, you'll need about 1 kg potatoes to yield this amount of mash)
• 50g (½ cup) parmesan cheese, grated
• handful of garlic croutons, bashed to uneven crumbs (optional)
• sea salt and freshly ground black pepper

METHOD

1. Preheat the oven to 160C fan-forced (180 conventional).
2. Put the butter and spring onions in a microwave-safe bowl and microwave for 3 minutes or until soft. Tip out into a 20 x 28cm baking dish.
3. Toss the fish pie mix with the cornflour and add to the dish with the spring onions. Combine the mustard, cream, fish stock, prawns, peas, most of the parsley and plenty of seasoning, then add the mixture to the pie dish and gently stir everything together to combine.
4. Spoon the mashed potato on top of the fish mixture and rough up the surface with a fork. Sprinkle over the parmesan cheese.
5. Bake for 30 minutes until the pie is hot through and golden on top. Scatter with the crushed garlic croutons, if using, and the remaining parsley. Serve immediately.

Make ahead Cool and freeze the pie for up to a month. Defrost and reheat as per the cooking instructions.

The shortcut Using cream and a little fish stock in place of a bechamel sauce saves you a good 15 minutes.

Serves 4, with leftovers

Self-saucing sticky toffee pudding

If I see sticky toffee pudding on a menu, I am only going through the motions of eating the main course in order to get to dessert faster, lest I be told "we've sold out of the sticky toffee pudding". It's happened to me so many times that I came up with this self-saucing recipe to streamline and speed up my own version of the pud.

What happens as this pudding cooks is nothing short of miraculous. As the cake bakes and rises, the wet ingredients sink to the bottom of the dish, making a rich toffee sauce that puddles underneath the sponge. No separate sauce-making required. Serve this soon after removing it from the oven, or the sauce will be reabsorbed.

INGREDIENTS

• 100g (generous ⅓ cup) butter, melted, plus extra for greasing
• 175g (generous 1 cup) soft dried pitted dates, chopped
• 75ml (5 tablespoons) boiling water
• 200ml (scant 1 cup) milk
• 3 large eggs, lightly beaten
• 75g (scant ½ cup) soft dark brown sugar
• 75g (⅓ cup) caster sugar
• 300g (2⅓ cups) self-raising flour
• 1 teaspoon baking powder
• ¼ teaspoon mixed spice
• ice-cream or cream, to serve

For the sticky toffee sauce

• 300ml (1¼ cups) boiling water
• 150g (generous ¾ cup) soft dark brown sugar
• 5 tablespoons double cream
• pinch of salt

METHOD

1. Preheat the oven to 160 fan-forced (180C conventional).
2. Grease a deep rectangular baking dish, 20 x 28 cm, with butter and place it on top of a baking sheet. Bring a kettle or a large pan of water to the boil.
3. Put the chopped dates into a jug and cover with the 75ml (5 tablespoons) boiling water. Leave to stand for 5 minutes or until softened, then use a hand-held stick blender to process until smooth. Add the melted butter, milk and eggs to the dates and stir to combine.
4. Put both types of sugar, flour, baking powder and mixed spice into a large mixing bowl. Pour in the date mixture and stir to combine. Scrape the mixture into the baking dish and smooth the surface with the back of a spoon.
5. Next, make the sticky toffee sauce. Measure out the 300ml (1¼ cups) boiling water in a measuring jug, then add the sugar, cream and a good pinch of salt. Stir until the sugar and salt have dissolved, then quickly pour the mixture all over the cake batter. Bake in the oven for 45 minutes until the top is set and the sauce is bubbling up around the edges.
6. Carefully remove the pudding from the oven and leave to stand for 5 minutes, then scoop out portions and serve with ice-cream or cream.

Make ahead

You can prepare the wet ingredients a few hours before you want to make the pudding, then just mix with the dry ingredients and continue as per usual.

Get a jug of the ingredients for the magic sauce ready to go when you prep the dry and wet ingredients and top up with boiling water from the kettle. This can't be reheated in the oven, but a very short blast in the microwave will warm the sponge and make the sauce softer again.

The shortcut As the pudding makes its own sauce, you are free from the additional faff of preparing the sticky-toffee element.

Serves 6-8

This is an edited extract from The Shortcut Cook by Rosie Reynolds, published by Quadrille, RRP $29.99. Photography: Louise Hagger. Buy now