- Preheat oven to 400 degrees. Grease a 9x9 baking dish.
- Cut the bacon up into pieces.(kitchen sheers work great for this)
- Add the butter to a skillet and melt. Cook the mushrooms and bacon together in the skillet. Bacon should be nice and cooked.
- Place the cooked mushrooms and bacon in the bottom of the baking dish.
- In a large bowl, whisk together the eggs, heavy cream, onion powder and salt and pepper. Stir in the cheese, leaving a little to sprinkle over the top of the casserole.
- Pour the egg mixture over the bacon and mushrooms. Sprinkle the top with the cheese that was left.
- Bake for 30 minutes or until the eggs are set and the top is golden brown.