For me, I've discovered that if I cook my beans the day before, drain them and refrigerate them, I get a better texture to my hummus for some reason.
I believe I started with 2 c of dried beans with my last batch, soak overnight, I overcook them so they puree easier, drain and refrigerate overnight.
In the FP I toss about half a dozen cloves of garlic, about a tsp of salt and the juice of half a lemon. Puree that until there are no chunks left. Add the beans and a generous amount of olive oil. Puree a bit, scrape down, puree a bit more. I add about 2 heaping spoonfuls (serving spoon, not cereal spoon, so at least 1/4 c) of tahini, puree a bit more. I needed the juice of 3 lemons, a lot of salt and at least 1/4 c of olive oil. Once the puree starts working nicely, I just let it run for several minutes, taste and adjust the salt and lemon juice as needed (if it needs more garlic, it needs to be pressed before adding). This made about 6 c of hummus - it filled a quart jar and a soup bowl.