spray 9 X 9 glass baking dish with cooking spray, preheat oven to 350.
gather all ingredients and needed utensils. Chop bacon in to small pieces. Then finely chop onions.
place bacon and onions into skillet. Place garlic in garlic press then put into skillet also. When bacon is almost cooked to your liking, add drained mushrooms. Cook for approximately 5 minutes more then drain and add this mixture to the bottom of the glass baking dish. Make sure to spread it around so it covers the bottom of the pan. Make sure you drain well or you will have a pool of grease on top of your frittata. If this happens, you can use a paper towel to absorb it before serving.
shred cheese. I used Vermont Sharp White Cheddar, or it's known as Hunters Cheese for the sharp bite, but you can use what ever cheese you have on hand.
mix eggs and half and half in a bowl. Season to taste with salt and pepper. You can add any other flavors your family likes, take note though that the bacon and the cheese can be pretty salty on it's own. Sir in the cheese you just shredded.
pour egg mixture into baking dish on top of meat mixture. Sprinkle with shredded cheese. I just used some leftover cheese from another recipe, any flavor will do. You could just shred some extra cheese when you are shredding the cheddar.
bake at 350 for 20 to 30 minutes, checking for doneness every 10 minutes or so. You will know it's done when your eggs are set up. This is like a souffle so it puffs up and then falls shortly after removing it from the oven.