Mashed Potatoes with Jerusalem Artichokes and Chives

Name: Mashed Potatoes with Jerusalem Artichokes and Chives
Yield: Makes 8 Servings
Ingredients: 2 tablespoons fresh lemon juice; 1 1/2 pounds Jerusalem artichokes (sunchokes); 3 pounds russet potatoes, peeled, cut into 2-inch pieces; 1 teaspoon salt; 1/2 cup crème fraîche or sour cream; 1/4 cup (1/2 stick) butter; 6 tablespoons chopped fresh chives