Wholemeal cake with sour cherry jam

INGREDIENTS
125 g white flour
125 g wholemeal flour
120 g butter
120 g granulated sugar
100 g walnut kernels
5 eggs
2 tablespoons cocoa
1 large apple or 2 small, preferably Renetta
1 sachet baking powder
A sachet vanillin
1 jar sour cherry jam
Whipped cream to serve if desired

I put softened butter, sugar and vanillin in a bowl.

I beat electrically.

I add yolks one at a time, reserving whites. Always use room-temperature eggs.

I add each yolk only once the last is combined, continuing to whisk.

Everything should be thoroughly whipped.

I combine white and wholemeal flour.

Then cocoa.

Then baking powder.

I sift all dry ingredients.

I grind walnuts in a processor.

I mix into flour.

I peel and grate apples.

Work quickly as they darken.

I beat apples into butter and eggs.

I gradually add dry ingredients.

They should combine thoroughly.

I whisk reserved whites.

I add first a few spoonfuls vigorously with a spatula, then gently fold in remaining whites upwards from bottom.

Once combined,

I put in a buttered, floured or parchment-lined 26 cm tin.

I bake at 180°C about 35/40 minutes, testing centre with a knife for a dry, clean result.

I cool slightly, remove and halve horizontally with a serrated knife.

I spread bottom with sour cherry jam.

I reassemble, dust with icing sugar and optionally serve whipped cream.