In large skillet, cook ground sirloin and onion over medium heat 8 to 10 minutes or until beef is no longer pink and onion is tender, breaking up meat with side of spoon.
Stir in tomato sauce, beans, corn, tomato paste, brown sugar, hot sauce, cumin and coriander, and cook 5 minutes or until heated through, stirring occasionally. Remove skillet from heat and stir in cilantro. Makes about 5 cups.
If desired, toast or warm buns. Split buns and evenly spoon meat mixture over bottom halves of buns; replace top halves and serve.