Story and recipe by Jess Whitehead @dearambrose:

This is the recipe for chocolate crunch. The smell of it cooking in the oven, this warm heady chocolate and vanilla combination, takes me straight home. I've been baking this with my mum ever since I was little and I can almost guarantee every time I go home to see my family (which hasn't been for some time now) that there will be a little tin of chocolate crunch waiting for me by the kettle.

Sometimes I bake it when I'm homesick, other times I just bake it because I've got the ingredients in my cupboards and no one can resist a little square of it with a cup of tea. It was a recipe handed down four generations and it has stood the test of time because it is simple, minimal, and absolutely delicious.

Ingredients
170g unsalted butter, melted, plus extra for the tin
1 tsp vanilla extract
170g caster sugar
225g self-raising flour
25g cocoa powder
1 large egg, beaten
2 tbsp granulated sugar

Method
1. Heat the oven to 180C/160C fan/gas 4. Butter a 20cm square tin and line with baking parchment. Stir the melted butter and vanilla together in a bowl. Mix the caster sugar, flour and cocoa together in another bowl.

2.Pour the bowl of wet ingredients into the dry and beat together, then add the egg and beat again until combined. Press into the prepared tin. Brush the top with water and sprinkle over the granulated sugar.

3.Bake for 30-35 mins. Leave to cool slightly in the tin for 5 mins before slicing into squares and transferring to a wire rack to cool completely.