Heat beef and beans separately until hot. Spoon about 1/4 cup of the beef onto center of each tortilla. Spoon about 2 tablespoons of the beans onto beef. Top with 1/4 cup of the lettuce and about 2 tablespoons each of the tomatoes and cheese. Fold bottom end of each tortilla up about 1 inch over filling; fold right and left sides over folded end, overlapping. Fold remaining end down.