This is based on a recipe from Sandra's blog, "Full Bellies, Happy Kids"; she has some truly amazing recipes and wonderful step-by-step pictures...you should check it out! The recipes are not gluten free, but I've successfully modified many of them for my gf household.
1/2 cup gluten free bread crumbs
2 lbs ground meat (I like to use 1 1/2 lbs ground beef and 1/2 lb ground pork)
1 teaspoon garlic powder
1 medium onion, chopped
salt and pepper to taste
1/3 cup ketchup
2 tablespoons Worcestershire sauce
cheese (I used sliced Jarlsberg & a mix of grated sharp and mild cheddars)
more ketchup for the top
Preheat oven to 350°. Spray large loaf pan or 8" x 10" casserole dish with non stick cooking spray.
In a large bowl, mix together meats, bread crumbs, eggs, garlic powder, onion, salt and pepper, Worcestershire sauce and ketchup. Don't over mix, just mix with your hands until everything is combined well.
Divide meat mixture in half. Press one half into the pan and pat smooth, then place the cheese slices and the shredded cheese on the meat layer
Top with second half of the meat mixture, and press all around the edges to seal the cheese inside. Drizzle ketchup over the top and then bake for about 60 minutes or until meat is done.