Ingredients

200g dark chocolate, broken into chunks
100g milk chocolate, broken into chunks
85g butter
100g light muscovado sugar
85g dark muscovado sugar
3 eggs, at room temperature and lightly beaten
140g plain flour
140g walnuts, roughly chopped
200ml natural yogurt

Method

1-Heat oven to 180C/fan 160C/gas 6 and line the base of a 20cm square shallow baking tin with baking parchment. Melt 100g dark chocolate, all of the milk chocolate and the butter in a heatproof bowl over a pan of simmering water. Remove from the heat, then stir in the sugars. Cool a little while you prepare the rest of the ingredients.

2-Stir the eggs into the chocolate mixture, followed by the flour, walnuts and a pinch of salt until really well combined. Pour the mixture into the prepared tin, then bake for 25-30 mins until an inserted skewer comes out with sticky crumbs. Cool in the tin.

3-For the dip, gently melt the remaining chocolate as above, then stir into the yogurt and chill. To serve, cut the brownies into chunks, then spoon the dip into small bowls.