Roll out the puff pastry (defrost if necessary) to the size of a quiche dish and lay out. Prick several times with a fork and let rest in the refrigerator for 30 minutes. Blind-bake in a preheated oven at 200 ° for approx. 15 minutes. Remove the peas and baking paper and bake for another 15 minutes.
Blanch the asparagus for 2-3 minutes, drain and cut into bite-sized pieces. Fry the onions in the hot oil until golden brown. Place the asparagus, onions and hazelnuts on the pastry base. Beat the cheese, eggs and cream until frothy, season well with salt and pepper and pour over the tart. Bake in the oven for another 15-20 minutes until the filling is firm. Can be served warm and cold.