Heat the oil in a pot set over medium heat. Add the onion, ginger and garlic and cook until tender, about 4 minutes. Stir in the flour and cook 2 minutes more. Slowly stir in the stock.
Mix in the pumpkin, apple, cumin and nutmeg. Simmer the soup 10 to 15 minutes. Puree the soup with a hand blender or in a food processor. Return to a simmer; season with salt and pepper. Ladle the soup into small glasses or cups, top with blue cheese and serve.