In a large skillet, sauté chopped whites of leek 5 minutes. Add in apples, cook two more minutes.
Add in 4 cups vegetable broth and the chopped sweet potato and pumpkin.
Add ½ tsp black pepper
Simmer 20 minutes.
Remove to a cool place before blending. Do not blend hot liquids. Do not overfill the blender, no more than 1/3 of the way up. When cooled, blend all of the product and reheat to barely a simmer.