Low-Carb Bacon, Egg, and Spinach Breakfast Casserole

INGREDIENTS

eggs

1 1/2 cups

egg whites

2 cups

spinach (frozen, thawed and drained)

slices nitrate-free bacon (cooked and crumbled)

1 cup

sliced mushrooms

1/2 cup

red onion (chopped)

1/2

green pepper (chopped)

1/2

red pepper (chopped)

1 71429/1000000 cups

shredded cheddar or 3 cheese mix

salt and pepper