Pumpkin in a chili sounds like a seasonal gimmick and it isn't — it breaks down into the sauce and thickens it, so you get body without the heaviness beef would bring. That's the actual reason it's there and it took a minute of explanation to make sense. The spices get toasted in the pan before the liquid goes in, which is the step that separates this from a tin. Skillet cornbread alongside is worth adding; it bakes while the chili simmers.
Julian