Prepare the crust. Using a food processor with the metal blade, whisk together the flour and salt.
Cut the cold butter into tablespoon-sized pieces and drop into the flour mixture. Process until the dough is crumbly.
Add 1 1/2 tablespoons ice water and process. If the dough begins to form a ball and move around the processor bowl, you have enough water. If it is still crumbly, add more ice water until it does form a ball.
Turn the dough out onto a piece of plastic wrap and pat it into a round about an inch thick. Wrap well and refrigerate for at least an hour. You can make the dough one day and bake it the next.
Saute the bacon and onions in a skillet with 1 tablespoon oil just until the onions are softened. Add a teaspoon of dried rosemary and saute another minute. Add the salt, white pepper, cayenne pepper, and nutmeg. You can do this step the day before as well if you like. Refrigerate if you do.
When you are ready to make the quiche, preheat the oven to 425 degrees F. Roll out the dough and fit it into a 9"- quiche or pie pan. Cover the pastry with aluminum foil, fill with pie weights or dried beans and bake for 10 minutes. Remove the foil and pie weights and bake 3 more minutes. Reduce heat to 325 degrees F.
Beat the 4 eggs in a large mixing bowl. Add the half & half and blend well. Stir in the bacon/onion mixture. Fold in the grated cheese.
Pour the filling into the pie shell and return to the oven. Bake 45-50 minutes until the pie is set firm.