Bring a pot of water to a boil and cook ramen noodles for about 3 minutes until tender. Drain and set aside.
In a large skillet over medium heat, cook chopped bacon until crispy. Remove bacon bits and set aside, leaving some fat in the pan.
Add ground beef and diced onion to the skillet. Cook until beef is browned and onions are soft, breaking up meat while cooking.
Stir in minced garlic and cook for one more minute.
Mix in ketchup, mustard, and optional pickle relish. Season with salt and pepper, stirring until combined and heated through.
Add cooked ramen noodles to the beef mixture and toss well to coat evenly.
Preheat oven to 375°F (190°C). Transfer noodle and beef mixture to a baking dish.
Sprinkle shredded cheese evenly over the top and scatter cooked bacon bits over the cheese.
Bake for 15 to 20 minutes until cheese is melted, bubbly, and edges are lightly golden.
Remove from oven and let cool slightly. Garnish with diced pickles or chopped green onions if desired. Serve warm.