Instructions

In the bowl of a food processor or blender, add the Creole mustard, green onions, horseradish, garlic, mustard, hot sauce, Worcestershire, lemon juice, egg, salt, and pepper. Process until smooth, about 30 seconds.
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With the motor running, slowly pour the vegetable oil into the blender or food processor in a slow, steady stream. Add the parsley and pulse to combine. Transfer to a container, fold in the chopped eggs and capers, cover, and refrigerate for 1 hour before using. This sauce will keep, refrigerated, for up to 24 hours.
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*RAW EGG WARNING
The American Egg Board states: "There have been warnings against consuming raw or lightly cooked eggs on the grounds that the egg may be contaminated with Salmonella, a bacteria responsible for a type of foodborne illness. Healthy people need to remember that there is a very small risk and treat eggs and other raw animal foods accordingly. Use only properly refrigerated, clean, sound-shelled, fresh, grade AA or A eggs. Avoid mixing yolks and whites with the shellÖ"
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Yield: 1 1/2 cups