Break the egg into a blender, add the mustard and 1/4 cup of the oil and pulse the blender for about 10 seconds. Then switch the blender to high speed & add about half the oil in a steady thin stream. The emulsion will be quite thick so now add the lemon juice & vinegar which will thin it slightly. Now add the Datils & wait until they are thoroughly blended in [10-15 sec] before adding the rest of the oil. Stop & taste & add salt to your preference--usually about 1/2 teaspoon or more for me. Some prefer all lemon juice or all vinegar but I like the flavors of both. Any good hot chile ought to work in this receipe. Enjoy! Posted to CHILE-HEADS DIGEST V4 #049 by Gene Dunnam <EDUNNAM@NERVM.NERDC.UFL.EDU> on Jul 30, 97