A quincey, appley, crumbly cake

A twist on the classic apple crumble.  The soft, melting quince acts as a hidden surprise here, with fudgy chunks of russet flesh concealed under a base of moist apple sponge.  The crumble topping isn't essential but gives a nice textural contrast to the sponge layer.

This is one of those sweets that is equally lovely served cold as a cake or hot as a pudding, perhaps stranded in a puddle of custard.

~for the cake

150g self raising flour
150g room temperature butter
150g golden caster sugar
½ tsp baking powder
2 medium eggs and 1 egg yolk
1 bramley apple (about 150g)
200g quinces, peeled, cored and cut into chunky slices
1 tbsp butter and 1 tbsp sugar to cook the quinces

~for the crumble

½ tsp ground cinnamon
50g plain flour
50g ground almonds
50g cold butter, cut into small cubes
2 tbsp oats
30g golden caster sugar

1) To make the cake: cream the butter and sugar, then beat in the eggs one by one.  Sift the flour and baking powder into the mixture, and fold in lightly.  Grate the apple in (peel and all) and gently stir into the mixture.

2) Sautee the quince slices in the butter and sugar for a few minutes, until slightly softened.  Line a 20cm square baking tin with a strip of greaseproof paper in both directions, with some hanging over the edge of the tin.  This will help to remove the cake after cooking.  Place the quince at the bottom of the tin, then spoon in the cake batter, and bake at 375f/190c/gas mark 5 for 25 minutes.

3) While the cake is in the oven, make the crumble topping by placing all the ingredients in a bowl and lightly rubbing together with your fingertips until it resembles coarse breadcrumb.  After the first 25 minutes of cooking, cover the cake with the crumble topping, working quickly so as not to disturb the cooking process.  Return the cake to the oven for a further 20-25 minutes, or until a toothpick poked in comes out clean.

4) Leave to cool a little before removing from the tin using the greaseproof paper 'straps', and cut into squares.