Food & Cooking Recipes Healthy Recipes Gluten-Free Recipes Mashed Potatoes and Celeriac 3.5 (20) 1 Review By Martha Stewart Test Kitchen Martha Stewart Test Kitchen The recipes developed by our test kitchen team have undergone a rigorous process of development and testing, ensuring that every element is optimal, from ingredient amounts to method and cooking time. This process includes triple-testing recipes to ensure they meet our high standards. The many stellar cooks and food editors who have been part of our team include Sarah Carey, Lucinda Scala Quinn, Jennifer Aaronson, Shira Bocar, Anna Kovel, Greg Lofts, Riley Wofford, Lauren Tyrell, and Lindsay Leopold. Editorial Guidelines Updated on May 16, 2017 Print Rate It Share Share Tweet Pin Email Photo: ANNA WILLIAMS Prep Time: 10 mins Total Time: 45 mins Servings: 4 Celeriac -- also called celery root or celery knob -- adds a twist to mashed potatoes. Ingredients 1 pound russet potatoes, peeled and sliced 1 ½ inches thick 1 pound celeriac, peeled and sliced 1 ½ inches thick Coarse salt ½ cup sour cream 2 tablespoons unsalted butter ¼ teaspoon freshly ground nutmeg Freshly ground pepper Directions Place potatoes and celeriac in a medium saucepan, and fill with enough cold water to cover by about 2 inches. Bring to a boil over high heat; add salt generously. Reduce heat to a simmer, and cook until vegetables are tender when pierced with a paring knife, 20 to 25 minutes. Drain in a colander. Pass potatoes and celeriac through a ricer or food mill into a serving bowl. Add sour cream and butter, and stir until combined. Stir in nutmeg, and season with salt and pepper. Serve immediately. Rate it Print