Combine meat and 1/4 cup enchilada sauce. Shape meat mixture into 4 (1/2-inch-thick) patties. Coat a nonstick skillet with cooking spray. Place over medium heat until hot. Add patties, and cook 4 to 5 minutes on each side or until done. Remove from skillet; drain on paper towels.
Spread 2 tablespoons refried beans on bottom half of each bun. Top each with 1/4 cup shredded lettuce, 2 tablespoons chopped tomato, and 2 tablespoons shredded cheese. Top each with a meat patty. Spoon remaining 1/4 cup enchilada sauce evenly over patties. Top with remaining bun halves.