Heat the olive oil in a large sauce pan over medium high heat.
Add the leeks and cook until fragrant, about 2 minutes.
Add the mushrooms, sage, chipotle powder, and salt and cook, stirring occasionally, for another 5 minutes.
Add pumpkin and chicken stock. Stir and bring to a boil.
Lower the heat to medium low and cook, covered, for 20-25 minutes, until the pumpkin is fork tender.
Carefully transfer to a blender. Add the milk and blend until smooth.
Divide into 6 portions. Serve each portion with 1 tablespoon of Greek yogurt, 1 teaspoon of pumpkin seeds, and chopped parsley.