Heat oil in a medium saucepan over medium heat and sauté onion until lightly browned, 6–10 minutes. Add garlic and cumin; cook for 30 seconds, stirring. Stir in tomatoes with juices, broth, andpumpkin; mix until smooth. Add chili powder, chipotle, oregano, and beans. Bring to a boil, reduce heat, and simmer, partly covered, for 15–18 minutes, until beans are soft and chili is thickened. Season with salt and pepper.

While chili cooks, heat a small skillet over medium-low and toast pumpkin seeds until they begin to brown and pop, 3–5 minutes, shaking pan frequently.

Serve chili hot, topped with pumpkin seeds, cilantro, avocado and sour cream or yogurt.