Sauté the Aromatics. Begin by setting your Instant Pot to the sauté mode. Melt the butter, then add chopped onions and garlic. Sauté for a few minutes until they become soft and fragrant.
Add the Spices. Sprinkle in the ground nutmeg, cinnamon, cayenne, salt, and pepper. Sauté for another minute to toast the spices, releasing their flavors.
Pressure Cook. Pour in the vegetable broth and pumpkin puree. Stir well to combine. Seal the Instant Pot, set it to pressure cook for 5 minutes, and let the magic happen.
Naturally Release Pressure. After the cooking cycle, allow the Instant Pot to naturally release pressure for about 10 minutes. Then carefully do a quick release.
Blend to Perfection. Use an immersion blender to puree the soup until it's silky smooth. If you don't have an immersion blender, you can transfer the soup to a regular blender in batches, then return it to the Instant Pot.
Creamy Finish. Stir in the heavy cream and let it heat through, ensuring the soup is perfectly creamy.
Serve and Garnish. Ladle your pumpkin soup into bowls and garnish with a drizzle of cream, a sprinkle of nutmeg, and a few pumpkin seeds for that extra touch of fall.