For the shortcrust pastry, mix the flour with the soft butter, the egg, salt and the baking powder until an even dough is formed. Shape the dough into a ball, wrap it in cling film and let it rest in the refrigerator for half an hour.
In the meantime, cut the vegetables into small pieces. Boil the broccoli briefly in boiling salted water for 3 minutes, then rinse in cold water (so it stays greener) and drain well. Briefly fry the kohlrabi and leek in a pan with olive oil so that light toasted aromas develop. Season everything with a little salt and pepper.
Now spread the dough thinly in a greased springform pan or deep baking dish. The thinner the batter, the better the quiche tastes. Put the fried vegetables on the dough and distribute evenly. With broccoli you should make sure that it has been dried well, otherwise the dough will become slightly soft!
For the topping, whisk the cream with the eggs and season to taste. Use enough salt, otherwise the vegetables will taste rather bland. Now pour the mixture over the vegetables and sprinkle the quiche with cheese.
Bake the quiche for 20 minutes at 180 ° C on top / bottom heat until the cheese is lightly browned on top. I always serve a delicious leafy salad with it.