NB: This will do one large tart or two smaller pie sized ones.

1. Sift the flour and rub in the margarine to make a breadcrumb consistency.

2. Mix in the egg yolk and sugar.

3. With a round ended knife, gradually mix in the water until you reach a nice doughy consistency. You might need more or less than the 2 tbsp specified.

4. Wrap in cling film and chill in the fridge for 15 mins or so before use.

5. Once the pastry has chilled, roll out to about half a centimetre thick on a well floured surface or between two pieces of cling film.

6. Grease a large flan dish and press the pastry into it. Line with greaseproof paper and add baking beans, blind bake on gas mark 5 for 15-20 minutes until the pastry is browned.

7. While the pastry is blind baking, place the cream and sugar in a pan and bring to the boil. Take the cream off the heat and add in the margarine and chocolate, stir until both have melted into the hot cream.

8. Once everything has melted together whisk with an electric whisk until thick and creamy

9. Pour the chocolate into the blind baked case and leave on the side to cool for a few hours, once cold enough place in the fridge and chill for at least 3 hours.

10. Once the milk chocolate layer is firm to touch you can make the caramel. Add the margarine, condensed milk and golden syrup to a pan, heat gently until it has all melted together and starts boiling, turn the heat down and keep stirring until the caramel turns golden brown. Cool slightly and pour on top of the chocolate layer, chill again for a few hours.

11. One the caramel is firm to touch, make the crumble for the top. Rub together all the ingredients, place on a baking tray and bake on gas mark 5 for 20-25 mins until it begins to brown.

12. When the crumble has baked, melt the white chocolate and pour on top of the caramel, sprinkle the crumble over the top and then refrigerate to set the chocolate. Leave the tart to chill for at least another hour however over night will ensure everything is well set before serving.