Add chickpeas, pumpkin puree, tahini, lemon juice, garlic, cumin, smoked paprika, and cayenne (if using) to a food processor.
Pulse until the mixture is well combined but still slightly chunky.
With the processor running, slowly drizzle in the olive oil until the hummus reaches your desired consistency. Add 1-2 tablespoons of water if needed for a smoother texture.
Taste and adjust seasonings with salt and pepper.
Transfer to a serving bowl, drizzle with additional olive oil, and sprinkle with pepitas.
Serve with pita chips, crackers, or fresh vegetables. Can be made up to 3 days ahead and stored in the refrigerator.