In a large pot or Dutch oven, brown the ground beef over medium heat until fully cooked. Break it apart with a wooden spoon as it cooks. Drain excess fat if necessary.
Add the chopped onion, minced garlic, and diced bell pepper to the pot. Cook for about 5 minutes, stirring occasionally, until the vegetables are softened.
Stir in the chili powder, cumin, paprika, salt, and black pepper. Cook for an additional minute to allow the spices to release their flavor.
Add the rinsed kidney beans and diced tomatoes (with their juice) to the pot. Stir well to combine.
If the chili appears too thick, add beef broth a little at a time until you reach your desired consistency.
Bring the chili to a simmer, then reduce the heat to low. Cover and let it cook for 30 minutes, stirring occasionally to prevent sticking.
Taste and adjust the seasoning if necessary; add more salt, pepper, or spices according to your preference.
Serve hot, and top with optional toppings like shredded cheese, sour cream, and diced green onions.