Sauce Maltaise

Instructions

1. Prepare the blood oranges
   Zest one blood orange and set the zest aside. Juice both oranges, straining out any seeds. Reduce the juice in a small saucepan over low heat until it measures about 3 tablespoons. Let cool to room temperature.
2. Create the egg yolk base
   In a heatproof bowl set over a pan of barely simmering water (don't let the bowl touch the water), whisk the egg yolks with 1 tablespoon of cold water and lemon juice until the mixture begins to thicken and ribbon when the whisk is lifted, about 3-4 minutes.
3. Incorporate the butter
   Remove the bowl from heat. Very slowly drizzle in the warm clarified butter while whisking constantly, starting with just a few drops and gradually increasing to a thin stream. The sauce should thicken and become smooth and glossy.
4. Add the blood orange elements
   Whisk in the reduced blood orange juice and reserved zest. The sauce should turn a delicate pink-orange color. If the sauce is too thick, whisk in a few drops of warm water to adjust the consistency.
5. Season and finish
   Add salt, cayenne pepper, and Dijon mustard (if using). Taste and adjust seasonings as needed. For extra stability, you can whisk in the optional tablespoon of heavy cream. Keep warm until serving by placing the bowl over a pan of warm (not hot) water.