Classic Creamy Horseradish Mashed Potatoes — Perfect Roast Beef Side

How to Make Classic Creamy Horseradish Mashed Potatoes — Perfect Roast Beef Side

1. 1

   Step 1: Start potatoes in cold salted water

   Place peeled, evenly sized Yukon Gold chunks in a large pot and cover with cold water by about 1 inch. Add 2 tsp kosher salt and bring to a gentle boil over medium-high heat, then reduce to a simmer and cook until potatoes are tender when pierced with a fork, about 12–15 minutes. Starting them in cold water ensures even cooking and prevents a gluey exterior.

   For this step

   • 2 1/2 lbYukon Gold potatoes, peeled and cut into 1–1.5" chunks
   • 2 tspKosher salt (for cooking water and seasoning)
   
2. 2

   Step 2: Drain and steam-dry, then add butter

   Drain potatoes in a colander and return them to the still-warm pot off the heat; set the pot over the empty burner for 30–60 seconds to let excess steam evaporate—this 'steam-dry' step removes extra water for fluffier mash. Add the butter pieces while the potatoes are hot; using a ricer or food mill produces the lightest texture. If you don't have those, use a sturdy potato masher and press gently—avoid overworking to prevent gummy potatoes.

   For this step

   • 6 tbspUnsalted butter, cut into pieces
   
3. 3

   Step 3: Warm dairy and fold in with horseradish and sour cream

   Warm the milk and heavy cream together until just hot (not boiling) and stir in the prepared horseradish and sour cream if using. Gradually fold the warm dairy mixture into the mashed potatoes a little at a time until you reach the desired creaminess; warming the dairy prevents cooling and helps it incorporate smoothly. Taste as you go—horseradish strength varies, so add more or less to suit your preference.

   For this step

   • 1 cupWhole milk, warmed
   • 1/2 cupHeavy cream, warmed
   • 2 tbspPrepared horseradish (adjust to taste)
   • 1/4 cupSour cream (optional, for tang and extra creaminess)
   
4. 4

   Step 4: Season, adjust texture, and finish

   Season with freshly ground black pepper and additional kosher salt to taste (remember the cooking water added salt earlier). If the mash is too stiff, thin with a splash more warm milk or cream; if too loose, fold in a little extra mashed potato or chill briefly to firm. Transfer to a warmed serving bowl, finish with a few extra knobs of butter if desired, and sprinkle with finely chopped chives for color and freshness.

   For this step

   • 1 tspFreshly ground black pepper
   • 2 tbspFresh chives, finely chopped (for garnish)
   
5. 5

   Step 5: Make-ahead and reheat instructions

   To make ahead: cool the potatoes to room temperature, cover tightly, and refrigerate up to 2 days. Reheat gently: transfer to an ovenproof dish, dot with butter, add 2–4 tbsp warm cream or milk, cover with foil and bake at 325°F (160°C) for 20–25 minutes, stirring once until piping hot. For stove or microwave reheating, warm slowly over low heat with extra cream and stir frequently to restore creaminess; for serving to a crowd, keep in a slow cooker on low with a little added cream and stir occasionally.
   

1. Place peeled, evenly sized Yukon Gold chunks in a large pot and cover with cold water by about 1 inch. Add 2 tsp kosher salt and bring to a gentle boil over medium-high heat, then reduce to a simmer and cook until potatoes are tender when pierced with a fork, about 12–15 minutes. Starting them in cold water ensures even cooking and prevents a gluey exterior.
2. Drain potatoes in a colander and return them to the still-warm pot off the heat; set the pot over the empty burner for 30–60 seconds to let excess steam evaporate—this 'steam-dry' step removes extra water for fluffier mash. Add the butter pieces while the potatoes are hot; using a ricer or food mill produces the lightest texture. If you don't have those, use a sturdy potato masher and press gently—avoid overworking to prevent gummy potatoes.
3. Warm the milk and heavy cream together until just hot (not boiling) and stir in the prepared horseradish and sour cream if using. Gradually fold the warm dairy mixture into the mashed potatoes a little at a time until you reach the desired creaminess; warming the dairy prevents cooling and helps it incorporate smoothly. Taste as you go—horseradish strength varies, so add more or less to suit your preference.
4. Season with freshly ground black pepper and additional kosher salt to taste (remember the cooking water added salt earlier). If the mash is too stiff, thin with a splash more warm milk or cream; if too loose, fold in a little extra mashed potato or chill briefly to firm. Transfer to a warmed serving bowl, finish with a few extra knobs of butter if desired, and sprinkle with finely chopped chives for color and freshness.
5. To make ahead: cool the potatoes to room temperature, cover tightly, and refrigerate up to 2 days. Reheat gently: transfer to an ovenproof dish, dot with butter, add 2–4 tbsp warm cream or milk, cover with foil and bake at 325°F (160°C) for 20–25 minutes, stirring once until piping hot. For stove or microwave reheating, warm slowly over low heat with extra cream and stir frequently to restore creaminess; for serving to a crowd, keep in a slow cooker on low with a little added cream and stir occasionally.