Preheat the oven to 200C/180C fan/Gas mark 6 and line a 12-hole muffin tin with cases. Sift the flour and baking powder into a bowl and stir in the sugar. Crack the egg into a separate bowl and whisk in the vanilla extract, milk and butter. Stir the wet ingredients into the dry and add the raspberries and chocolate, take care not to over mix. Spoon the mixture into the cases and bake for 25-30 minutes and bake until well risen and just firm to the touch.