Mayonnaise

1 egg
½ t salt
½ t mustard powder
2 T cider vinegar
1 c oil

Put egg, salt, mustard & vinegar in blender with ¼ c oil. Blend on low, uncover and slowly but steadily pour in remaining oil. Atmospheric conditions will occasionally cause mayonnaise to curdle as you’re making it. If this happens, remove it from blender, put another egg in blender, turn it on and slowly pour in curdled mayonnaise.