Prep your heat source. If using a campfire, get it going until you have a good bed of hot coals (not roaring flames). If using a grill, preheat to medium-high. If civilization-bound, preheat your oven to 400°F.
Tear off four pieces of heavy-duty aluminum foil, about 18 inches long each. If you only have regular foil, use a double layer—trust me on this one.
In a large bowl, combine the sliced sausage, potatoes, bell peppers, onion, and green beans.
Drizzle with olive oil and sprinkle with garlic powder, Italian seasoning, smoked paprika, red pepper flakes (if using), salt, and black pepper. Toss everything together until evenly coated. The oil is important here—it prevents sticking and helps everything roast rather than steam.
Divide the mixture equally among the four pieces of foil, placing it in the center of each.
Top each pile with 1 tablespoon of butter and a sprig of fresh herbs if using.
Fold the foil to create secure packets: bring the long sides together above the food and fold them down together, leaving some space for steam. Then fold in the shorter ends to seal completely. You want it tight enough to keep juices in but with a little room for steam circulation.
Place packets on hot coals, on a grill grate, or on a baking sheet if using an oven. Cook for about 20-25 minutes, flipping halfway through if possible (use tongs!).
Check for doneness by carefully opening one packet (watch out for escaping steam!). The potatoes should be tender when pierced with a fork, and the sausage should be browned.
Serve directly in the foil for the authentic camping experience, or transfer to plates if you're feeling fancy.