Heat the olive oil in a large pot over medium heat. Add the onion and garlic, cooking until softened, about 5 minutes. Increase the heat to medium-high and add the ground meat to the pot. Cook, breaking it apart with a spoon, until browned and cooked through.
Stir in the pumpkin puree, diced tomatoes, broth, black beans, kidney beans, chipotle peppers, chili powder, cumin, and smoked paprika. Season with salt and pepper to taste.
Bring the chili to a boil, then reduce the heat to low. Simmer, uncovered, for at least 45 minutes to an hour, stirring occasionally. The chili should thicken and flavors meld together.
Taste and adjust seasoning as needed. Serve hot, with optional garnishes of sour cream, shredded cheese, green onions, or cilantro on top.