Heat oil in 6-quart saucepan. Add ground beef, onions and garlic and saute until meat is browned. Stir in next 7 ingredients and bring to boil over medium-high heat. Reduce heat to medium-low and simmer, uncovered, about 45-55 minutes. Taste and season with salt, pepper and cayenne pepper, if desired. Ladle into bowls. Garnish with cheese, onion and avocado, if desired. Makes about 8 cups.