Melt 2 tablespoons of butter in a large skillet over medium-low heat. Add 2 sliced yellow onions and cook gently for about 20 minutes until golden.

Cook 8 slices of bacon in another skillet over medium heat until chewy for about 8-10 minutes. Remove and let cool before chopping.

Preheat your oven to 400°F (200°C). Roll out the deep-dish pie crust and place it into a deep pie pan.

In a mixing bowl, whisk together 8 large eggs, 1½ cups of heavy cream, salt, and pepper. Fold in the caramelized onions, bacon, and cheese.

Pour the filling mixture into the prepared pie crust. Bake for 40-45 minutes, then remove foil and bake an additional 10-15 minutes.

Let the quiche rest for 10-15 minutes before slicing for easier cutting.