Butternut Squash Soup

1 butternut squash, peeled and cut into 1-inch chunks
Nutmeg
2 tablespoons unsalted butter
Salt and pepper
1 onion, chopped
4 cups chicken stock

In a large pot melt butter. Add onion and cook until translucent, about 8 minutes. Add squash and stock. Bring to a simmer and cook until squash is tender. Remove squash chunks with slotted spoon and place in a blender and puree. Return blended squash to pot. Stir and season with nutmeg, salt and pepper. Serve.