Preheat oven to 225oc and grease a 250mm x 200mm oven dish.
Lots of rhubarb (5-8 stalks)
1tsp vanilla sugar
2tsp potato flour
Peel and chop the rhubarb in to small chunks and place in the oven dish. Mix the sugar, vanilla and potato flour and sprinkle over the rhubarb and give it a quick mix.
125g melted butter
75ml muscovado sugar
100ml plain flour
80g grated marzipan
50g ground almonds
Place all the dry ingredients in a mixing bowl and mix well. Add the melted butter and mix to a dough/crumble. Flatten the dough in your hands and place over the rhubarb in bits until it is covered.
Bake in the middle of the oven for 20minuts or until the top looks crispy and golden.