In a large soup pot, sauté onions in butter until tender. Add squash, chicken stock, marjoram, black pepper and cayenne pepper. Bring to boil; simmer 20 minutes, or until squash is tender.
Purée squash and cream cheese in a blender or food processor in batches until smooth. Return to saucepan and heat through. Do not allow to boil. Season with salt as needed.
While soup is reheating, place frozen Simplot UpSides Hearty Grains & Wild Mushrooms in a microwave-safe 4" deep dish and cover. Heat on high for 7 minutes. Rotate the dish and stir thoroughly halfway through cook time. Let stand 1 minute. (Microwaves vary; check that the blend has reached 165°F.)
To serve, pour one cup (8 oz.) of soup into a bowl and garnish with 3 oz. Simplot UpSides Hearty Grains & Wild Mushrooms, pomegranate seeds and fried sage leaves, if desired. Serve hot.