Ingredients
1 3/4 cups homemade or low-sodium store-bought chicken stock
1 cup water
1 pound celeriac (also called celery root), peeled and cut into 1-inch pieces
1 pound Yukon gold potatoes, peeled and cut into 1-inch pieces
1 medium Granny Smith apple, peeled, cored, and cut into 1-inch pieces
1 medium shallot, coarsely chopped
1 dried bay leaf
Coarse salt
2 tablespoons unsalted butter, room temperature
3/4 ounce blue cheese (about 2 tablespoons), such as Buttermilk Blue, Danish blue, or Roquefort, plus more for crumbling
Preparation
Bring stock, water, celeriac, potatoes, apple, shallot, bay leaf, and 1 teaspoon salt to a boil in a large pot. Cook until tender, about 10 minutes. Strain, reserving liquid; discard bay leaf. Return celeriac, potatoes, apple, and shallot to pot, and add 3/4 cup reserved cooking liquid. Coarsely mash with a potato masher.
Using a fork, mash together butter and blue cheese in a small bowl. Stir into celeriac mixture. Season with salt.
Spoon into a warm serving bowl, and crumble blue cheese over top.
