Heat oil in a large saute pan over medium-high heat. Add the ground beef, onion and garlic and cook for about 7-10 minutes or until the beef is completely browned, crumbling the beef with a spoon as it cooks. Drain and discard the excess fat/grease. Then transfer the beef into the bottom of a slow cooker. Add the remaining ingredients, and stir to combine. Cover and cook on low for 6-8 hours, or on high for 3-4 hours. Taste, and season with additional salt and pepper or seasonings if need be. Serve warm, with desired toppings.
