Step 1Heat the oven to 350 degrees.
Step 2In a large bowl, combine the hamburger, ground bison and elk or venison. Add the red and green pepper, the onion, bread crumbs, egg, steak seasoning and marinara. Mix the ingredients with your hands, kneading well to thoroughly incorporate. Cover and refrigerate until needed.
Step 3Line a 9-by-5-by-3-inch loaf pan or dish with bacon. Pack the meatloaf mixture into the dish, then very gently invert onto a 9-by-13-inch baking dish. Sprinkle over a pinch each of kosher salt, freshly ground pepper and granulated garlic.
Step 4Bake the meatloaf for 1 hour, then increase the heat to 400 degrees and continue to bake the meatloaf until the bacon is crisp and a thermometer inserted in the center of the meatloaf reaches 165 degrees, 15 to 30 minutes (timing will vary depending on how quickly the oven heats). Remove and set aside for at least 10 minutes before serving.