In a large pot or Dutch oven over medium heat, add your ground beef or turkey. Use a wooden spoon to break it apart as it cooks. Stir occasionally until it's nicely browned and cooked through.
Once your meat is browned, push it to one side of the pot. Add the diced onion and bell pepper to the other side. Sauté them for about 5 minutes until they are tender and fragrant.
Add in the minced garlic and stir everything together. Cook for another minute until you can smell that delicious aroma wafting through your kitchen.
Pour in the diced tomatoes along with their juices and add the tomato sauce. Stir well to combine everything.
Add in your beef broth next. Once that's integrated well, toss in both types of beans (kidney and pinto). Gently stir everything together.
Sprinkle in your chili powder, cumin, paprika, cayenne pepper (if using), salt, and black pepper. Give your chili a good stir to ensure that all those spices are evenly distributed.
Bring your chili mixture to a gentle boil over medium-high heat. Once boiling, reduce the heat to low and let it simmer uncovered for about an hour.