These smooth, creamy, innocent-looking mashed potatoes deliver an exhilarating hit of horseradish. Prep and Cook Time: 1 1/4 hours. Notes: You can also make this with horseradish root, which can be wonderful if you find a good fresh one. Use 1/2 cup finely grated fresh horseradish, add it to the heated cream-milk mixture, and let steep off the heat for 30 minutes before adding it to the potatoes. The potatoes can be made a couple of hours ahead and then gently reheated in the microwave.
5 pounds russet potatoes, peeled and chopped into 1-in. pieces
1 3/4 cups whipping cream
1 cup milk
1 stick unsalted butter (1/4 lb.)
4 to 6 tbsp. cream-style prepared horseradish (see Notes)
About 1 tbsp. kosher salt
About 1/4 tsp. white pepper
How to Make It
Bring a large pot of water to boil. Add potatoes, lower heat to a simmer, and cook until very tender, about 25 minutes. Drain potatoes and return to pot over low heat. Stir over heat until completely dry and starting to fall apart (this will make them soft and light when puréed).
Meanwhile, heat cream and milk in a heavy-bottomed pot over medium-low heat until just simmering. Put potatoes, butter, and horseradish into bowl of a standing mixer with paddle attachment and beat on low until nearly smooth. While beating, drizzle enough cream-milk mixture into potatoes to make them soft and loose, keeping in mind that potatoes stiffen as they sit around (you may not need all the milk and cream). Add salt and white pepper to taste and beat just until smooth (avoid overbeating, as purée will become gummy).