Creamy Mustard Sauce

This creamy mustard sauce is perfect with Scotch eggs, fried fish, and steamed or grilled vegetables like asparagus. For the best texture and appearance, use a smooth traditional dijon mustard and white pepper. This sauce is best served warm the day it is made, but can be kept in the refrigerator overnight and gently reheated the next day.

This recipe makes 1 to 1½ cups of sauce.


  • 2 tablespoons butter
  • 2 tablespoons flour
  • salt and pepper to taste (preferably white pepper)
  • 1 teaspoon finely chopped parsley
  • 1 teaspoon finely chopped tarragon
  • 1 – 1¼ cups half-and-half
  • 1 tablespoon Dijon mustard


  1. In a small saucepan over medium-low heat, melt butter.
  2. Whisk in flour; cook for about 1 minute, whisking constantly, until smooth and bubbling.
  3. Add seasonings, then add 1 cup of half-and-half a little at a time.
  4. Continue whisking until thickened; add more half-and-half until desired consistency is reached.
  5. Whisk in mustard; serve warm.