01 - Preheat your campfire grate, outdoor grill, or oven to medium-high heat, targeting approximately 400°F.
02 - In a mixing bowl, combine the ground beef with garlic powder, onion powder, smoked paprika, a generous pinch of salt, and black pepper. Mix gently just until the seasonings are evenly distributed, being careful not to overwork the meat.
03 - Divide the seasoned beef mixture into 4 equal portions and shape each into a flat, even patty.
04 - Tear 4 large sheets of heavy-duty aluminum foil, approximately 12 inches per side. Brush the center of each sheet with olive oil to prevent sticking.
05 - Arrange thinly sliced potatoes in the center of each oiled foil sheet. Top with layers of onion, red bell pepper, and mushrooms. Season the vegetables lightly with salt and pepper.
06 - Place one beef patty on top of the vegetable bed in each packet. Drizzle each patty with 1/2 tablespoon of ketchup and a small dab of yellow mustard.
07 - Fold the foil edges together tightly to form sealed packets, crimping the seams securely to trap steam and prevent any leaks during cooking.
08 - Place the sealed packets on the campfire grate, grill grates, or in the oven. Cook for 20 to 25 minutes, flipping once halfway through, until the beef is cooked through and the vegetables are fork-tender.
09 - Carefully open each foil packet, watching for hot steam. Place a slice of cheddar cheese on each patty, then reseal the packets and let them rest for 2 minutes to allow the cheese to melt.
10 - Serve the packets directly from the foil or transfer to plates. Garnish with sliced dill pickles, chopped lettuce, fresh tomato slices, and additional condiments as desired.