Combine ground beef, jalapeno peppers, cumin, salt and pepper; mix lightly but thoroughly. Divide beef mixture into 4 equal portions; shape into 1/2 inch thick patties, 4 inches in diameter. Place patties on grid over medium coals. grill 7 to 9 minutes, turning once. Sprinkle 1 tablespoon cheese on each burger 1 minute before end of cooking time. Place tomato slice on bun bottom; top each with grilled burger and cover with roll top. To check temperature, cautiously hold hand about 4 inches above coals, Medium coals will force removal of hand in 4 seconds.