In a skillet over medium heat, brown the ground beef until fully cooked. Drain any excess grease.
Add the cooked ground beef to the slow cooker.
In the same skillet, sauté the diced onion, bell pepper, and minced garlic until softened (about 3-4 minutes).
Transfer the sautéed vegetables to the slow cooker with the ground beef.
Add the diced tomatoes (with juice), kidney beans, black beans, corn, chili powder, cumin, paprika, salt, black pepper, cayenne pepper (if using), and broth to the slow cooker.
Stir all ingredients together until well combined.
Cover the slow cooker and cook on low for 6 hours or high for 3 hours until the chili is hot and flavors have melded.
Once cooking is complete, taste and adjust seasoning if necessary.
Serve the chili hot, with toppings such as shredded cheese, sour cream, green onions, or avocado.