Big Mac Breakfast Pie

Preheat the oven to 350°F.
In large oven-safe skillet, over medium heat. Add the ground beef, onions, and garlic and season with 1 1/2 teaspoon salt. Cook while crumbling with a wooden spoon until the beef is cooked all the way through and the onions are translucent, about 7 minutes. Add the tomato sauce and stir well to combine.
In large bowl, mix together the eggs, cheese, mayo, mustard, 1/2 teaspoon salt, and pepper.
Add the beef mixture to the egg mixture and stir to combine. Pour the mixture into a greased 9x13 casserole dish. I sprayed mine with Primal Kitchen Avocado Oil Spray.
Place the dish in the oven and bake for 25 minutes, or until the eggs are cooked through in the center. Remove from the oven and let rest for 10 minutes, then slice and serve. If desired, garnish with fresh sesame seeds and pickles and serve with secret sauce. Store leftovers in an airtight container in the fridge for up to 3 days. Reheat in a 350°F oven for 3 minutes or in the microwave for 30 seconds, or until heated through.