1. Mix the Cayenne and mustard to a paste with a little of the vinegar, then stir in the rest of the vinegar. Beat in theoil. Season to taste with salt and a generous amount of freshly ground pepper. Add the remaining ingredients and stir to mix. This is a very liquid sauce.
2. The solids should float in the bowl, so add a little more oil and vinegar if necessary. It is very hot.