1Remove casing from sausage; crumble sausage into medium bowl. Add onion, bell pepper and potatoes; mix well. Shape mixture into 6 patties, about 1 inch thick.
2In 12-inch nonstick skillet, heat oil over medium heat. Cook patties in oil 13 to 16 minutes, turning once or twice, until thermometer inserted in center of patties reads 165°F.
3Top each patty with 1 slice cheese. Cover; let stand 1 minute until cheese is melted. Serve on toasted muffins.