Prep the Vegetables: Begin by dicing the onion and red bell pepper, and mincing the garlic. Set aside.
Brown the Chorizo: Heat a large pot over medium heat. Add the ground chorizo sausage and cook, stirring occasionally, until browned and crumbly, about 5-7 minutes. Once cooked, use a slotted spoon to remove the chorizo, leaving the rendered fat in the pot.
Sauté the Vegetables: In the same pot, add the olive oil, diced onions, and red bell peppers. Sauté until the onions are translucent and the peppers have softened, about 5 minutes. Add the minced garlic and cook for an additional minute until fragrant.
Combine Ingredients: Return the browned chorizo to the pot. Stir in the pumpkin puree, diced tomatoes, beef broth, chili powder, ground cumin, smoked paprika, and cayenne pepper. Season with salt and pepper to taste.
Simmer the Chili: Bring the mixture to a boil, then reduce the heat to low and simmer uncovered for 45 minutes to an hour, stirring occasionally. The chili should thicken and the flavors will meld together.
Garnish and Serve: Once the chili is thickened to your liking, remove from heat. Ladle into bowls and garnish with fresh cilantro if desired. Serve hot.