Cook bacon in a large skillet over med-high heat until crisp. Remove the bacon from pan with a slotted spoon, and set on a paper towel lined plate. Reserve the bacon grease in the pan.
Place the ground beef, onion and garlic into the same skillet that you cooked the bacon in, over medium-high heat. Break the beef apart with a wooden spoon and brown the beef for 7-10 minutes. Transfer the ground beef mixture into a colander to discard any excess liquid. Return the meat to the pan (still over medium/high heat). Toss in riced cauliflower, salt and pepper until incorporated.
Add the liquid aminos, diced tomato, cream cheese, pickle, mustard and half of the reserved bacon. Stir the mixture together and cook until cream cheese is melted throughout.
Spray a 13x9 baking dish (or 3 quart casserole dish) with cooking spray. Pour the ground beef mixture into the dish. Sprinkle the top with cheddar cheese and the remaining bacon. Bake for 15-20 minutes, until cheese is melted and casserole is bubbling.
Top with chopped parsley if desired.
This recipe makes 9 servings, which will come out to be approximately 1 cup per serving.