In a blender or food processor, combine the egg yolk, soy sauce, Creole mustard, Worcestershire, salt, and pepper, and process for 20 seconds on high speed.
With the machine running, add the oil through the feed tube in a steady stream and process until it is smooth and thick.
Adjust the seasoning, to taste.
*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 shell."