We found celery root and Jerusalem artichokes equally delicious in this puree.

Ingredients

　　2 pounds russet (baking) potatoes

　　2 pounds celery root, peeled and cut into 2-inch pieces, or Jerusalem artichokes (sunchokes), peeled and halved

　　2 whole carrots, peeled

　　3/4 stick (6 tablespoons) unsalted butter

　　In a kettle combine the potatoes, peeled and halved, the celery root or Jerusalem artichokes, and the carrots with cold water to cover and simmer the vegetables, covered, for 25 to 30 minutes, or until they are tender. Reserve 1 cup of the cooking liquid and drain the vegetables in a colander. Force the potatoes through a ricer into a large bowl or mash them in the bowl with a potato masher. In a food processor puree the celery root or the Jerusalem artichokes with the butter until the mixture is smooth and stir the mixture into the potatoes. Using the coarse side of a grater shred the carrots into the bowl and combine the mixture well, adding salt and pepper to taste and enough of the reserved cooking liquid to achieve the desired consistency. The puree may be made 1 day in advance and kept covered and chilled.