Makes 10 cups
8 tablespoons (1 stick) salted butter
2 cups coarsely chopped onion
2 cups peeled, cored, and coarsely chopped granny smith apple
2 cups peeled and coarsely chopped turnip
2 cups peeled and coarsely chopped butternut squash
2 cups coarsely chopped carrot soup
2 cups peeled and coarsely chopped sweet potato
10 cups salted chicken stock
1 teaspoon kosher salt, plus salt to taste
1/2 cup grade A or B maple syrup
Cayenne to taste
Melt the butter in a large stock pot over moderately high heat.
Add the onion and saute until translucent, about 5 minutes. Add the apple, turnip, squash, carrot, sweet potato, stock, and 1 teaspoon salt.
Cook stirring occasionally, for 30 to 35 minutes, or until the vegetables are tender.
Use a hand blender to puree the soup in the pot. (If you dont have a hand blender, pour the soup into a food processor and puree in batches.)
Transfer the pureed soup back to the pot and add the maple syrup and cayenne. Season to taste, bring the soup to a simmer, and serve.