Food & Cooking Recipes Breakfast & Brunch Recipes Hollandaise with Mustard and Horseradish Be the first to rate & review! By Martha Stewart Test Kitchen Martha Stewart Test Kitchen The recipes developed by our test kitchen team have undergone a rigorous process of development and testing, ensuring that every element is optimal, from ingredient amounts to method and cooking time. This process includes triple-testing recipes to ensure they meet our high standards. The many stellar cooks and food editors who have been part of our team include Sarah Carey, Lucinda Scala Quinn, Jennifer Aaronson, Shira Bocar, Anna Kovel, Greg Lofts, Riley Wofford, Lauren Tyrell, and Lindsay Leopold. Editorial Guidelines Updated on October 9, 2013 Print Rate It Share Share Tweet Pin Email Servings: 6 The addition of spicy mustard and horseradish make this hollandaise from chef Michel Roux's "Sauces" cookbook a perfect compliment to broiled fish dishes.Also Try:Classic Hollandaise Sauce, Maltaise Sauce Ingredients 17 tablespoons (2 sticks plus 1 tablespoon) unsalted butter 1 tablespoon white wine vinegar 1 teaspoon white peppercorns, crushed 4 large egg yolks Coarse salt Juice of 1/2 lemon 1 tablespoon English mustard powder 1 tablespoon cold water 1 tablespoon freshly grated horseradish Directions Melt butter in a small saucepan over medium heat; slowly bring to a boil, skimming froth from surface. Carefully pour melted butter into a small bowl, holding back the milky sediment in the bottom of the pan. The clarified butter should be the color of light olive oil; let cool to room temperature. In a medium heavy-bottomed saucepan, mix vinegar together with 1/4 cup cold water and crushed peppercorns. Place over medium-high heat until liquid is reduced by one-third; remove from heat and let cool completely. Add egg yolks to cooled reduction and whisk to combine. Place saucepan on a heat diffuser over very low heat; whisk, making sure the whisk comes in contact with the bottom of the pan. Gradually increase heat whisking, so the sauce emulsifies progressively and becomes smooth and creamy, 8 to 10 minutes; do not let the temperature of the sauce rise above 150 degrees. Remove saucepan from heat and whisk in clarified butter in a slow, steady stream; season with salt. Stir in lemon. Line a chinois or fine mesh strainer with cheesecloth; strain mixture and discard solids. Mix together mustard powder and water; stir into hollandaise sauce along with horseradish. Use sauce immediately. Rate it Print