Cook bacon in a skillet until crispy, then remove, crumble, and set aside.
Drain most bacon grease, leaving about 1 tablespoon in the skillet, then add ground beef, onion, and garlic.
Cook until beef is browned and onion is soft; stir in smoked paprika, garlic powder, salt, and pepper.
Reduce heat and stir in softened cream cheese until melted and incorporated.
Add crumbled bacon back into the beef mixture and spread evenly into a greased 9x13-inch baking dish.
In a mixing bowl, whisk eggs, heavy cream, mustard, and optional ketchup.
Stir in half of the cheddar and mozzarella cheeses into the egg mixture.
Pour the egg mixture over the beef layer and top with the remaining cheddar and mozzarella cheeses.
Bake in a preheated oven at 350°F (175°C) for 25 to 30 minutes, until set and golden on top.
Let the casserole cool slightly before slicing; garnish with pickles or parsley if desired.