Journalist Sarah Wilson, who made her name with I Quit Sugar diet programs and sugar-free recipe books, has a new cause. Her latest book, I Quit Sugar: Simplicious Flow, embraces zero-waste cooking and nutritious eating with "capsule cooks" – menu plans for several days that use up the entire list of ingredients.

This capsule cook is all about showcasing the best of vibrant spring produce. Take one frisky lamb shoulder and tons of veg and you've got family dinners for three – yes, three – nights.

SUNDAY

Roast lamb with pea gremolata

We kick off with a Sunday roast. We whack in extra veg while we're there and have lots of lovely flavour going on for later ...

INGREDIENTS

2kg lamb shoulder, bone in

6 cloves garlic, minced

½ bunch thyme

2 tbsp extra-virgin olive oil, plus extra

1 lemon, halved

sea salt and freshly ground black pepper

2 leeks, halved lengthways

½ head cauliflower, cut into florets

2 zucchini, sliced into 2cm thick rounds

4 corn cobs, sliced into 2cm thick rounds

4 cups leafy greens (silverbeet, kale, spinach etc)

1 tsp apple cider vinegar

Pea gremolata

500g frozen baby peas, thawed

3 sprigs mint, leaves picked

4 sprigs flat-leaf parsley

big pinch of sea salt

2 tbsp extra-virgin olive oil

pinch of freshly ground black pepper

METHOD

1. Preheat the oven to 160C (140C fan-forced).

2. Place the lamb in a large roasting tin. Use a sharp knife to make slits in the meat and shove in the garlic and thyme. Drizzle over the olive oil, squeeze over the juice of half a lemon (dump in the skin, too) and season with salt. Roast for 4½ hours.

3. Remove from the oven and place the leek in the base of the roasting tin, submerging it in the lamb juices. Scatter over the cauli, zucchini and corn. Drizzle the vegies with a little olive oil and season with salt and pepper. Return to the oven and cook for a further 45 minutes, or until the vegies are tender and the meat falls off the bone.

4. Transfer the lamb to a plate or large bowl and allow to cool slightly before pulling the meat from the bone – you should get about 5 cups of meat. Set aside 2 cups for tonight's dinner and store the remainder in the fridge.

5. Meanwhile, to make the pea gremolata, place the ingredients in a blender or food processor along with the juice of the remaining lemon half. Blitz until almost pureed, leaving a few chunks for texture. Place half the gremolata in a container for tomorrow. Take out half each of the cauli, zucchini and corn and pop in a container for tomorrow. Toss the salad greens with the vinegar and a dash of olive oil.

6. Serve the shredded roast lamb alongside the dressed salad greens, roast leek and reserved roast cauliflower, zucchini and corn with the gremolata spooned over the top.

Serves 4 (with leftover lamb and leftover vegies)

MONDAY

Roast lamb tacos

INGREDIENTS

extra-virgin olive oil, for frying

12 mini corn or flour tortillas

2 cups leftover lamb

leftover roast cauliflower

leftover roast zucchini

leftover roast corn, kernels sliced off

leftover pea gremolata

4 cups leafy greens

3 large tomatoes, cut into chunks

1 cup Greek-style organic plain yoghurt

¼ cup flat-leaf parsley and/or mint leaves

Quick red onion pickle

1 small red onion, thinly sliced

¼ cup apple cider vinegar

pinch of sea salt

METHOD

1. To make the quick red onion pickle, mix all the ingredients in a small bowl and set aside for 10-15 minutes. Drain, reserving the juice.

2. Heat a drizzle of olive oil in a large frying pan over medium heat. Warm the tortillas in batches, turning to heat on both sides. Transfer to a serving plate.

3. Heat another glug of olive oil and add the lamb, cauli, zucchini and corn and cook for a few minutes to warm through. Break up the cauli and zucchini a little as you go.

4. Place the pan on the table along with the pea gremolata, pickle, tortillas, greens, tomato, yoghurt and fresh herbs in separate bowls and let everyone help themselves.

Serves 4

TUESDAY

Deconstructed Moroccan tagine with cauli couscous

INGREDIENTS

½ head cauliflower

2 carrots

1 onion

3 cloves garlic, peeled

1 zucchini

extra-virgin olive oil, for frying

1½ tbsp Ayurvedic Spice Blend (or use 1 tbsp garam masala mixed with 2 tsp ground cumin)

1 cup leftover lamb

1½ cups cooked chickpeas or 1 x 400g can chickpeas

2 large tomatoes, diced

1 orange, flesh chopped into 2cm chunks

sea salt and freshly ground black pepper

To serve

½ cup roughly chopped mint

½ cup roughly chopped flat-leaf parsley

¹⁄³ cup mixed pitted olives, roughly chopped

1 long red chilli, sliced

½ cup flaked almonds, roasted if you like

1 cup Greek-style organic plain yoghurt

METHOD

1. Push the cauliflower and carrot and separately through your food processor grater unit and set aside in separate bowls.

2. Fit the slicing attachment and push though the onion, garlic and zucchini. Set aside.

3. Heat a good glug of olive oil in a large frying pan over medium heat. Add the grated cauliflower and cook, stirring, for 4 minutes or until softened. Remove from the pan and set aside.

4. Add another glug of oil to the pan. At medium heat, add the onion, garlic and zucchini and cook for 5 minutes, or until softened. Add the spice, lamb, chickpeas, tomato and 1 cup water. Cook for 3-4 minutes. Stir through the orange and simmer for a further 10 minutes, or until the mixture thickens. Season to taste with salt and pepper.

5. Divide the cauli couscous among four plates, spoon over the lamb mixture and serve with the grated raw carrot, mint and parsley leaves, olives, chilli, almonds and yoghurt.

Serves 4

Recipes from I Quit Sugar: Simplicious Flow by Sarah Wilson, published by Pan Macmillan, RRP $45.