Rinse apples and rhubarb. Remove the cores and cut the apples and
rhubarb into smaller pieces.
Crumble flour, sugar, vanilla sugar and butter together so that
the mixture becomes like large breadcrumbs.
Grease an ovenproof dish with olive oil. Put apples and rhubarb in
the bottom and spread the crumble mixture on top. Roughly chop the
almonds and spread them on top of the cake. Bake the cake in the
oven for 30-40 minutes.
Serve the cake with a dab of sour cream. Bon appetite!