Add your bacon to a large skillet and cook until crisp. Remove, drain on paper towels, then crumble into small pieces.
Leaving a little of the bacon grease in the pan, sauté the mushrooms and onions for 3-5 minutes. Add in the garlic and sauté for about 20 seconds, careful not to burn it. Remove and set aside.
Preheat oven to 375F.
Using the same pan, add in the ground beef and brown. Drain well, then mix in the onions, mushrooms and garlic.
In a mixing bowl, whisk together the eggs, ketchup, mustard, 1 cup of the shredded cheddar cheese, Worcestershire, cream cheese, heavy cream and most of the bacon (reserve a little for garnish). Mix for about 2 minutes using a hand mixer (or whisby hand, until well combined.
Pour ground beef mixture into a 9 x 13 casserole baking dish that’s been sprayed with non-stick spray, and spread evenly. Pour the egg mixture over the top and mix in with the ground beef mixture, making sure it’s evenly distributed.
Top with the remaining cheese and bake for 25-30 minutes or until the cheese is slightly golden. Allow to cool slightly before serving. Store leftovers in the fridge in an airtight container for a few days or freeze.
Optional: serve with lettuce, tomato, pickles, ketchup, mustard and/or any other burger toppings that you like.