Preheat oven to 200°C and line a 12 hole muffin tin with papers or silicone liners.
Place butter and sugar into the Thermomix bowl and blend 6 sec/speed 6.
Insert Butterfly. Whip 1 min/Butterfly/speed 3.
Add eggs and vanilla and whip 1 min/Butterfly/speed 3. Remove Butterfly.
Add milk, flour and salt and just combine 20 sec/Interval. Over mixing will make muffins tough and rubbery, a lumpy mixture is fine.
Using a spatula, fold through the chocolate and raspberries. Divide between muffin tray and bake 20 minutes or until bouncing back when pressed gently.
These will freeze really well, but you should warm them up slightly before serving.