Preheat oven to 350°F (175°C) and grease a 9x13 inch baking dish.
In a large skillet over medium-high heat, brown the ground beef and onion until the meat is no longer pink. Drain excess fat.
Stir in the minced garlic and cook for 1 minute until fragrant.
Spread the beef mixture evenly into the prepared baking dish.
In a medium mixing bowl, whisk together eggs, heavy cream, mayonnaise, Worcestershire sauce, salt, and pepper.
Stir 1 cup of the shredded cheddar cheese into the liquid mixture.
Pour the egg and cheese mixture over the ground beef in the baking dish.
Top the casserole with the remaining 1 cup of cheddar cheese and the chopped bacon.
Bake for 30 minutes until the cheese is melted and the center is firm to the touch.
Allow to rest for 5 minutes before serving.