Place the ground beef in a bowl and mix it with 1½ tablespoons of the chili powder until evenly seasoned.
Add the seasoned beef to a large, heavy-bottomed pot over medium-high heat. Add the diced onion, jalapeño, and minced garlic.
Cook until the beef is browned and the onion has softened, breaking the meat into small pieces as it cooks. Carefully drain excess fat if necessary.
Add the green bell pepper, remaining chili powder, cumin, crushed tomatoes, kidney beans, diced tomatoes with their juices, beef broth, tomato paste, and optional brown sugar.
Stir everything together thoroughly and bring the mixture to a gentle boil.
Reduce the heat and simmer uncovered for 45–60 minutes, stirring occasionally. The Best Chili Recipe is ready when the sauce has reduced to your preferred thickness and the flavors have blended together.
Taste and season with salt and freshly ground black pepper as needed.
Serve hot with your favorite toppings, such as shredded cheddar cheese, sliced green onions, fresh cilantro, diced avocado, or a spoonful of sour cream.