Brown the meat in a large pot or Dutch oven over medium-high heat, breaking it apart with a wooden spoon until no longer pink, about 5-7 minutes. If using plant-based meat, follow package instructions for best results.
Add the onion and bell pepper to the pot and sauté until softened, about 4-5 minutes. Add the garlic and cook for another 30 seconds until fragrant, being careful not to burn it.
Stir in all the spices (chili powder, cumin, pumpkin pie spice, oregano, cinnamon, and cayenne) and cook for 1 minute to toast the spices and release their flavors.
Add the pumpkin puree and stir well to combine with the meat and vegetable mixture. The pumpkin should coat everything evenly.
Pour in the diced tomatoes with their juice and broth, stirring to combine. Then add both types of beans and the maple syrup or brown sugar.
Bring the chili to a simmer, then reduce heat to low. Cover and cook for 20-30 minutes, stirring occasionally to prevent sticking.
Taste and adjust seasonings as needed, adding salt, pepper, or more spices to suit your preference. If the chili is too thick, add a bit more broth; if too thin, simmer uncovered for a few more minutes.
Serve hot in bowls with your choice of toppings. A dollop of sour cream and sprinkle of toasted pumpkin seeds creates the perfect fall presentation.