Side Dish: United States – Dijon-Chive Celery Root and Potato Mash

Food safety reminder: Follow safe food-handling practices and use a food thermometer to verify safe internal cooking temperatures.

Serving Size: 4

Approximate Time

Prep 15 min

Cook 20 min

Total 35 min

Ingredients

U.S. measurements first, metric equivalents in parentheses. Conversions are approximate; oz means weight ounces, not fluid ounces.

1 lb (450 g) russet potatoes, peeled and cut into 1-inch (2.54 cm) chunks
1 lb (450 g) celery root (celeriac), peeled and cut into 1-inch (2.54 cm) chunks
1 garlic clove, smashed (optional)
4 tbsp (60 g) unsalted butter, plus more to taste
1 / 2 cup (120 ml) buttermilk, warmed (or whole milk)
1 1 / 2 tbsp (22 ml) Dijon mustard
2 tbsp (8 g) finely chopped fresh chives
1 tsp (5 ml) kosher salt, plus more to taste
1 / 2 tsp (2.5 ml) freshly ground black pepper

Show original ingredient measurements

1 lb / 450 g russet potatoes, peeled and cut into 1-inch chunks
1 lb / 450 g celery root (celeriac), peeled and cut into 1-inch chunks
1 garlic clove, smashed (optional)
4 tbsp (60 g) unsalted butter, plus more to taste
1 / 2 cup (120 ml) buttermilk, warmed (or whole milk)
1 1 / 2 tbsp (22 ml) Dijon mustard
2 tbsp (8 g) finely chopped fresh chives
1 tsp kosher salt, plus more to taste
1 / 2 tsp freshly ground black pepper

Instructions

U.S. measurements first, metric equivalents in parentheses. Conversions are approximate.

Place the potatoes, celery root, and garlic in a large pot and cover with cold, well-salted water by about 1 inch (2.54 cm).
Bring to a boil, then reduce to a gentle simmer and cook until very tender, 15 to 20 minutes.
Drain thoroughly and return the vegetables to the hot pot over low heat for 1 to 2 minutes to evaporate excess moisture.
Mash to desired smoothness. In a small saucepan, melt the butter and warm the buttermilk.
Stir the butter and buttermilk into the mash, then fold in the Dijon and chives.
Season with salt and pepper, adjusting consistency with a splash more buttermilk if needed. Serve hot.

Place the potatoes, celery root, and garlic in a large pot and cover with cold, well-salted water by about 1 inch.
Bring to a boil, then reduce to a gentle simmer and cook until very tender, 15 to 20 minutes.
Drain thoroughly and return the vegetables to the hot pot over low heat for 1 to 2 minutes to evaporate excess moisture.
Mash to desired smoothness. In a small saucepan, melt the butter and warm the buttermilk.
Stir the butter and buttermilk into the mash, then fold in the Dijon and chives.
Season with salt and pepper, adjusting consistency with a splash more buttermilk if needed. Serve hot.