Place a large pot or Dutch oven over medium heat and add the olive oil. Once shimmering, toss in the diced onion and red bell pepper. Sauté the vegetables for about 5 to 7 minutes until they soften and the onions become translucent. Add the minced garlic during the last minute of cooking, stirring constantly to prevent it from burning.

Increase the heat slightly and add the ground turkey to the pot. Use a wooden spoon to break the meat into small crumbles. Cook the turkey until it is fully browned and no longer pink. If there is an excess of liquid or fat in the bottom of the pot, feel free to drain it, though lean turkey usually requires very little draining.

Stir in the chili powder, cumin, smoked paprika, cinnamon, salt, and pepper. Let the spices toast with the meat for one minute to release their oils. Add the pumpkin puree, crushed tomatoes, black beans, kidney beans, and broth. Stir everything together until well combined. Bring the liquid to a gentle boil, then reduce the heat to low. Cover the pot and let the chili simmer for at least 30 minutes to allow the flavors to meld together.

Taste the chili and adjust the salt or spices if necessary. If the chili is too thick, add a splash more broth; if you prefer it thicker, let it simmer uncovered for an additional 10 minutes. Ladle the hot chili into deep bowls. Garnish with a dollop of sour cream, a sprinkle of cheese, and fresh cilantro for a beautiful presentation.