Bisque:

In
a large pot cook the onions and carrots in the butter over medium heat until
the onion is softened. Add the mace, ginger, white pepper, squash and the
sweet potatoes, and 4 cups of the broth, and simmer the mixture, covered, for
30 minutes, or until the vegetables are very soft. In a blender, puree the
soup in batches, transferring it as it is pureed to a pot. Stir in the
remaining 2 cups of broth. Season the bisque with salt and white pepper to
taste.

For
the Croutons:

Adjust
oven rack to the middle position and heat the oven to 350 degrees. Toss the
bread cubes with melted butter in a medium bowl. In a small bowl, combine
cinnamon and sugar; sprinkle over the bread cubes and toss to combine.

Spread
the bread cubes in a single layer on a parchment-lined baking sheet and bake
until crisp, 8 to 10 minutes (The croutons can be stored in an airtight
container for several days.) Sprinkle over soup just before serving.

To
serve:

Divide
the hot soup into soup bowls and top with cinnamon sugar croutons.

Makes 12 cups – serves: 8 to 12