Barefoot Contessa's Mustard Horseradish Sauce

Saw this on the Contessa's show on the Food Network last night. She serves it with a standing rib roast. I think it has many possibilities, perhaps as a base for a dip with chipped beef? The whole-grain mustard adds great texture. I made this for Christmas to go with " Da Best" Chicago-Style Italian Beef ("da Best" Chicago-style Italian Beef) and it was a heavenly combination. This made a lot so I took one and a half cups of the sauce, added about one cup of shredded sharp cheddar cheese and 3 chopped hard-boiled eggs. It was a lovely dip for crackers.

• Ready In: 5 mins
• Yields: 2 cups

Ingredients

• 1 1⁄2 cups mayonnaise, the good kind
• 3  tablespoons Dijon mustard
• 1 1⁄2 tablespoons  whole grain mustard
• 1  tablespoon  prepared horseradish
• 1⁄3 cup sour cream
• 1⁄4 teaspoon kosher salt

Directions

1. Whisk together the mayonnaise, mustards, horseradish, sour cream, and salt in a small bowl.