Preheat oven to 400 degrees F (200 degrees C).
In a medium bowl, mix the bacon, onions, and both cheeses. Place this mixture in the unthawed pie crust.
Mix the eggs and half and half in a bowl. Pour the egg mixture over the cheese mixture.
Bake in preheated oven for 15 minutes. Reduce heat to 350 degrees F (175 degrees C) and bake for an additional 35 minutes, until top of quiche begins to turn brown.