Brown the turkey: Heat olive oil in a large skillet over medium-high. Add ground turkey and cook, breaking it up with a spoon, until no longer pink and lightly browned, 6–8 minutes. Season with a pinch of salt and pepper.
Transfer to the slow cooker.
Sauté the aromatics: In the same skillet, add onion, bell pepper, and celery. Cook 4–5 minutes until softened. Stir in garlic for 30 seconds.
Transfer everything to the slow cooker.
Add the base: Stir in diced tomatoes, crushed tomatoes (or sauce), black beans, pinto/kidney beans, chicken broth, hot sauce, and tomato paste.
Season it up: Add chili powder, cumin, smoked paprika, oregano, onion powder, cayenne (if using), 1 teaspoon salt, and black pepper. Stir well to combine.
Slow cook: Cover and cook on Low for 6–8 hours or on High for 3–4 hours. The flavors will meld and deepen over time.
Finish with buffalo flair: About 15 minutes before serving, stir in the butter until melted for that authentic buffalo richness.
Add lime juice if you like a bright finish. Taste and adjust seasoning or hot sauce.
Serve: Ladle into bowls and top with blue cheese crumbles or cheddar. Garnish with green onions or cilantro.
A light drizzle of ranch or blue cheese dressing is great if you love that classic combo.