In a large soup pot, heat the olive oil over medium-high.
Add the yellow onion and garlic. Saute until the onion is translucent (approximately 5 minutes).
Add the squash and continue to saute for 2 to 3 minutes, stirring often.
Add the chicken broth, pumpkin puree, nutmeg, crushed red pepper, salt, and cumin. Stir well to combine.
Bring the soup to a near-boil over medium-high heat, then lower heat to medium-low and allow the soup to simmer for 15 minutes uncovered.
Using an immersion blender, blend the soup smooth then add more salt and crushed red pepper to taste (and heat preference).
Serve topped with roasted pumpkin seeds (optional).