1. Preheat the oven to 400F. Place a baking tray to heat for about 15 minutes.
2. Grease a 7 inch baking tin with oil.
3. In a measuring cup, mix together, egg, milk, salt, pepper and mustard.
4. Place the onions in a bowl and microwave for a couple of minutes.
5. In a 7 inch cake tin, place the rolled quick pastry, add onions and cheese.
6. Lightly beat the egg mixture and pour in onto the baking dish. Decorate with cherry tomatoes.
7. Transfer to the heated baking tray. Bake at 400F for about 20 to 3 minutes. Allow to cool slightly.
8. Serve with mashed potato and your favorite beverage.
This crisp short crust pastry and a just-set no-cream cheesy and onion filling is a good perfect for dinner parties, Sunday brunches, pot lucks, picnics and even afternoon tea. You can whip up this tasty, homemade quiche in no time and serve it warm or cold.