Place a spoonful of the mixture into each muffin hole and make an indent in the centre. Drop a teaspoon of Craig's Black Doris Plum Jam on top. Cover the jam with the remaining mixture. Smooth the tops with the back of a teaspoon. Bake for approx 18-20 minutes until they are golden and spring back when pressed. Remove from the oven and allow to cool in the tin for 5 minutes.