Heat the olive oil in a large pot or Dutch oven over medium heat. Add the diced onion and sauté for about 5 minutes until softened.
Add the minced garlic and cook for an additional 1-2 minutes until fragrant.
Add the ground beef (or turkey) to the pot. Cook, breaking it up with a wooden spoon, until browned and cooked through (about 5-7 minutes).
Stir in the chili powder, cumin, smoked paprika, cayenne pepper, salt, and pepper. Cook for 1-2 minutes to toast the spices.
Add the drained kidney beans, black beans, diced tomatoes (with their juices), pumpkin puree, and broth. Stir well to combine.
Bring the mixture to a boil, then reduce heat to low. Cover and simmer for 30 minutes, stirring occasionally.
Taste the chili and adjust seasoning if necessary. If the chili is too thick, add more broth to reach your desired consistency.
Serve hot, garnished with optional toppings like sour cream, shredded cheese, or chopped green onions.