Grind the mustard seed to the texture of a fine meal. Blend with dry mustard. Add water and blend thoroughly Set aside for at least an hour and as many as three hours, stirring occasionally. Scrape the mixture into a blender or food processor and add the remaining ingredients. Blend smooth. Taste, and add a bit more of the raspberry vinegar if it seems warranted. Remember the mustard will mellow somewhat. Store in a clean dry jar, tightly capped, in a cool dark place or the refrigerator for a week before using.