Heat olive oil in a large pot over medium-high. Add onion and chopped apple, and cook, stirring occasionally, until onion is beginning to brown and softened, about 10 minutes. Add garlic and thyme, and cook, stirring often, until fragrant and slightly browned (not burned), about 1 to 2 minutes.

Stir in pumpkin puree; cook, stirring occasionally, until puree turns a couple of shades darker.

Stir in chicken stock, maple syrup, salt, nutmeg, cinnamon, curry powder, and chicken base. Bring to a simmer over medium-low. Simmer, uncovered, and stirring occasionally, until slightly reduced and flavors meld, about 30 minutes.

Add the heavy cream. Use a stick blender to purée the soup until completely smooth.*

Taste and adjust seasoning with salt, pepper, and chicken base.

Ladle the soup into bowls and garnish with a swirl of cream (see note below) and chopped parsley, if desired.