1Coat baking dish with cooking spray. Brown ground sirloin and onion in large skillet, stirring til ground sirloin is crumbly. Drain. Add chili sauce, tomato sauce tomato paste and sherry. Season with salt and pepper. Simmer til heated through.
2Heat tortillas according to package directions. Fill them with the ground sirloin mixture. Mix the cheddar and Monterey Jack cheeses in a bowl. Sprinkle some of the cheese mixture over the ground sirloin mixture. Roll up tortillas and put in baking dish.
3Preheat oven to 350.
Spread any extra ground sirloin mixture over the tortillas. Top with remaining cheddar and jack cheeses. Bake for 20 to 25 minutes or til cheese is melted. Serves 12 to 16