Mix the butter, flour, egg yolk and cold water by hand or into the food processor. Work quickly and do not knead the dough.
Cover the dough tightly in food wrap and put in the fridge for half or 1 hour.
Heating the oven to 190℃ (375°F).
Roll out the dough and put in the quiche pan. Press the pastry into the form and lightly prick the bottom with a fork.
Bake for 10 minutes.
Quiche filling
While the quiche pastry bakes, make the quiche filling.
Mix the egg, egg white, double cream, salt and ground black pepper.
Sprinkle the baked quiche pastry with the swiss chard, spirng onions and bacon.
Pour the eggs-cream mix into the quiche pastry case.
Sprinkle with grated cheese on the top.
Put back in the oven and bake for 30 minutes.
Notes
The eggs, egg white, double cream, salt and ground pepper are the basic of the quiche filling, but you can put it everything what you want. The asparagus, spinach, seafoods, onion, pumpkin, tomato, peppers or jalapeno also are good in the quiche.