7 oz plain flour
3 oz lard or butter or hard vegetable fat
1/2 teaspoon salt
3 tablespoons water
1/2 lb sliced onions
2 oz butter or olive oil
1/2 pint milk
Make shortcrust pastry with the first set of ingredients, or, if you Don't Do Pastry, buy frozen shortcrust and thaw.
If you don't know shortcrust, here's how: sift the flour and salt into a bowl. Warm the fat until it's softish, and slice into the flour. With fingertips, rub the fat into the flour until it's the consistency of soft breadcrumbs. Add the water. Cut the water into the pastry with a broadbladed knife. When it's incorporated, knead the dough briefly on a floured board, and let it rest in a cool place for 20 minutes. While it's resting, lightly grease two 8-inch tart cases. Roll out the chilled pastry until it's thin, and drape over the tart cases. Push the pastry down into each case and trim off at the edges with a sharp knife. Bake the cases blind for 15 minutes at Gas 5 (375 F). Remove the cases from oven and allow to cool.
Fry the sliced onions in the butter or oil until a deep golden brown. Let them cool. Beat the eggs with the milk and enough salt to season until thoroughly mixed. Share the fried onions between the cases, pour over the egg and milk mixture, sprinkle Cayenne atop.
Bake for 20-30 minutes at Gas 4 (345 F) until the eggs are thoroughly set and the top is just beginning to brown. Cool before eating.