(adapted from here)
For the dough:
250 g flour
250 g ground almonds (or hazelnuts)
250 g cold butter, cut in cubes
250 g sugar
1 teaspoon of cinnamon
6 cl sherry (or rum)
200 g red currant jam (alternative: rasperry jam, but red currant is the real one)
1 egg yolk, stirred with
1 tablespoon of milk
This is what you do:
The dough: Mix the flour with the almonds, heap it on the worktop and form a well in the middle. Put the butter cubes and all the other ingredients in. Knead it rapidly to a soft shortcrust pastry. Form a ball, wrap it in cling film and put it in the fridge for an hour.
Butter a spring form. Preheat the oven to 180° C.
Roll out half of the dough and put it in the form. Distribute the jam generously on it, but leave a finger thick space on the edge free.
Form finger thick strips out of the other half of the dough and lay them on the edge and on top. (Half of them diagonally so that it looks like a grid.)
Brush it with the egg yolk-milk-mixture and put it in the oven. Bake for about 50-60 minutes.