I made the tonic after Christmas inspired by your posts and recipe posted right before that. Unfortunately, I couldn't find horseradish (why is that??) so in my desperation I bought the canned one. Everything else is organic tough. Shortly after I made the tonic I became ill with a sinus infection. I couldn't wait for the tonic to 'cure' so i started eating it out of the jar. I wanted the heat to hit my sinuses so I figured if I put it on bread i would chew it a bit longer than without. It tasted pretty good, not so hot though. I do miss the fresh horseradish. The canned one doesn't have the necessary punch. In any case, it is pretty good for a first time.
As I kept chewing my bread I thought i could use a little base for my hot slurry so I put some hummus on the bread. Now that was tasty. I think the man who used butter couldn't think of another base for his tonic, so he might have used butter out of necessity.
I can't say that it helped with the sinuses. I also took oil of oregano and that made me tear, sneeze, cough and blow my nose. After a lot of herbs I can say that I beat the monster within seven days. Usually it takes over two weeks. Thanks for posting the recipe. It'll be useful during the winter. My next canned winter staple will be sauerkraut.