Foryoueats: Corned Beef and Cabbage with Horseradish Cream Sauce

Ingredients

• For the Corned Beef and Vegetables:
• 1 (4-lb) flat-cut corned beef with seasoning packet (do not trim the fat)
• 4 tablespoons unsalted butter, melted
• 2 tablespoons prepared horseradish
• 1½ teaspoons salt
• ¼ teaspoon ground black pepper
• 6 medium carrots, cut into 2-in chunks
• 1¼ lb small gold potatoes (about 2.5" in diameter), halved
• 1 very small green cabbage, cored and cut into ½-inch-thick slices (see note)
• 2 tablespoons chopped Italian parsley, for garnish (optional)
• For the Horseradish Cream Sauce:
• 1 cup sour cream
• 2 tablespoons prepared horseradish, plus more to taste
• 1 tablespoon Dijon mustard
• 1 teaspoon white wine vinegar
• ¼ teaspoon salt
• ¼ teaspoon sugar