Preheat your oven to 375°F (190°C).
In a skillet over medium heat, cook chopped bacon until crisp. Remove with a slotted spoon and drain on paper towels.
In the same skillet, sauté the diced onion in the bacon drippings until soft and golden, about 5-7 minutes.
In a medium bowl, whisk together eggs, heavy cream, salt, pepper, and nutmeg.
Spread the cooked bacon and onion evenly over the bottom of the blind-baked pie crust.
Sprinkle shredded cheese on top of the bacon and onions.
Pour the egg mixture evenly over the fillings.
Bake the quiche for 45–50 minutes, or until the center is just set and the top is golden.
Cool for at least 15 minutes before slicing and serving. Serve warm or at room temperature.