I usually bought the frozen block packages of chopped broccoli and stuck the whole thing into a french fry basket that fit perfectly into the pot I was using. (easy to lift out and be left with only the broth) Used about 700ml of water and boiled for 7 minutes. The diet you are currently on should be a perfect complement to this. I never really had any of the food irritations that a lot of IC patients get, mainly things like vitamins will make me burn. Drink this stuff while warm - if you think the Epsom Salts are bad, cold broccoli juice will make you leave the house when you smell it. I did a batch of this twice a day on an empty stomach.
The mix is powerful enough it will show results within a couple days. I have no idea why it works exactly, but a while back, Professor Saracoglu finally listed a breakdown of what the broth consisted of and it was pretty incredible.