Pour the milk and cream into a saucepan with the castor sugar, spices and vanilla pod and seeds. Bring to the boil, remove from heat, then sit to infuse for 1/2 hour. Pass through a fine strainer.

Use a deep ceramic baking dish with a 1-litre capacity that can also be placed in a deep roasting tin with water for gentle cooking. Lightly brush the sides and base of the baking dish with some of the softened butter.

Cut each bun from top to bottom into five slices. Butter the cut sides.

In a clean bowl, whisk the eggs and egg yolks together. Warm the milk mixture again. Gradually pour it over the eggs while whisking and mix until well combined. Strain through a fine sieve.

Leaving the skin on, finely slice the apples into 4-5mm rounds so the core is in the centre of each slice. Select the larger slices – you will need about 30 – and remove any seeds.

Arrange the bun slices interspersed with apple slices. Pour the infused milk slowly into the dish, a third at a time, allowing the bread to soak it up. Stand for 10 minutes, until the liquid is fully absorbed. Sprinkle over demerara sugar.

Place in a roasting tin and pour hot water from a kettle to halfway up the sides of the baking dish. Preheat oven to 140C and bake uncovered for about 40 minutes, until pudding is just set and top is lightly browned. Remove from roasting pan and stand for 10 minutes before serving.

Video: How to make hot cross buns