In a large pot or dutch oven, brown the ground beef and season with a little salt, pepper, garlic powder.
After cooking a couple minutes, add the chopped onion and bell pepper. Keep sautéing until beef is cooked and veggies are softened.
Stir in the garlic, cumin, chili powder, salt, black pepper, and cinnamon.
Stir in the tomatoes, kidney beans, black beans, pumpkin puree, and chicken broth.
Bring to a boil over medium-high heat. Reduce the heat, cover, and let simmer, stirring occasionally, until the flavors meld, about 20 minutes.
Season to taste with salt and pepper.
Serve with cornbread, cheese, sour cream, and roasted pumpkin seeds if desired.