Preheat the oven to 180C/gas mark 4.  Line a muffin tray with paper cases.

Whisk together the eggs, caster sugar, soured cream and lemon zest.

Peel and chop the apple and stir into the egg mixture.

Sift in the flour, baking powder and cinnamon and gently fold together.

Spoon into the muffin cases and top with a few raspberries and a sprinkling of caster sugar. 

Bake for about 30 minutes or until well risen, golden brown and firm when pressed lightly with the fingertips.  Dust with icing sugar before serving.