This recipe (as with most of mine) is part science and part guestimating, and personal taste. I made mustard last year, and like the idiot I can be, I lost my notes. It was a full grain mustard mixed from 2 separate recipes, and the result was amazing. Shame. This time I went a totally different route, and did some more research before making this batch. Last time it was too acidic, and a lot of compensating had to be done. I think the problem was soaking the whole seeds in just straight up vinegar, instead of adding some water or other liquids, and over soaking the seeds.