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, kosher salt, and black pepper. Gently mix 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 roughly the width of your foil sheets.
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 a bed of thinly sliced potatoes in the center of each oiled foil sheet. Layer sliced onion, red bell pepper, and mushrooms evenly over the potatoes. Season the vegetables lightly with salt and pepper.
06 - Place one seasoned ground beef patty on top of the layered vegetables in each foil packet. Drizzle each patty with approximately 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 firmly to ensure no juices escape during cooking.
08 - Place the sealed packets directly on the campfire grate, grill grates, or oven rack. Cook for 20 to 25 minutes, flipping once halfway through, until the beef is fully 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 rest for 2 additional minutes to allow the cheese to melt.
10 - Serve the hobo packets directly from the foil or transfer to plates. Garnish with sliced dill pickles, chopped lettuce, fresh tomato slices, and extra ketchup or mustard as desired.