Cook the Meat: Heat a drizzle of olive oil in a large skillet over medium heat.
Add the chopped onion and sauté until softened, about 3–4 minutes.
Stir in the ground beef and Italian sausage, cooking until browned. Drain any excess fat.
Assemble the Chili: Transfer the meat mixture to the bowl of your slow cooker.
Add the chili beans, Ro*Tel, tomato paste, celery, garlic, bell pepper, roasted red peppers, and chopped bacon.
Season: Sprinkle in chili powder, salt, black pepper, paprika, sugar, oregano, cumin, basil, and cayenne pepper.
Pour in beef stock, hot pepper sauce, and Worcestershire sauce.
Stir everything together until well combined.
Slow Cook: Cover and cook on LOW for 8 hours (recommended for best flavor).
If short on time, simmer on the stovetop for at least 2 hours, though the flavor won’t be quite as rich as the slow cooker version.
Serve: Ladle chili into bowls and top with Fritos, sour cream, shredded cheddar, and diced onion.