Simplest Butternut Squash Soup

For the soup

butternut squash (about 3 lb )

slender or 1½ larger leeks, white parts only, split lengthwise, washed, and cut into 1-inch-long pieces

whole milk

water

Salt and freshly ground pepper

Fresh grated nutmeg

Optional garnish

tart apple, white parts only, split lengthwise, washed, and cut into 1-inch-long pieces peeled, cored, and cut into tiny dice

About ⅓ cup chopped toasted hazelnuts or walnuts

About ½ cup crème fra໬he or heavy cream