Season your boiled potatoes generously with seasoning salt and pepper. Add sliced green onions, about 1T per burrito to your potatoes and stir to combine. Add your browned breakfast sausage and throw all of that into a plastic zipper bag or portable container. Refrigerate until you are ready to pack your cooler. Store in your cooler until ready to make burritos.
At the campsite, warm a frying pan on your cookstove. Add the potato/sausage mixture to the hot pan, stirring often, until potatoes begin to brown and mixture is heated through. Add beaten eggs to potato mixture and cook until eggs are scrambled.
Meanwhile, lay out large squares of foil, each with a tortilla on top. If using refried beans, spread a thin layer of refried beans onto the middle of each tortilla. Top with potato/sausage/egg mixture. Sprinkle cheese on top of that.
Fold your burrito then roll each burrito up in foil and place over the campfire. Cook your burritos, flipping once, about 5 minutes per side (depending on the heat of your campfire) or until cheese is melted and burrito is heated completely through (the tortillas will get some browning and charing on them, which is good, just watch carefully that you don't burn them).