Raspberry & dark chocolate teacakes

Name: Raspberry & dark chocolate teacakes
Prep time: 1 h
Cook time: 25 min
Total time: 1 h 25 min
Cuisine: British
Ingredients: 200g dark chocolate , finely chopped; freeze-dried raspberry pieces, to decorate (optional); 100g butter , softened; 75g icing sugar; 1 medium egg yolk; 1 tsp vanilla extract; 2 tbsp milk; 175g plain flour; 4 tbsp cocoa powder; 3 gelatine leaves; 3 medium egg whites; 175g white caster sugar; good-quality raspberry jam