I used to used canned beans as a base and build from there, however i got to thinking (can be dangerous) that if i am going to cook a piece of meet for 12 hours why not spend that much time cooking a really good pot of beans. I start with dried white beans. I soak them for a few hours and just make the sauce up a little runny. As it cooks in the smoker the beans keep soaking up the flavor. I also found putting the pot under the butts in the smoker helped as all the rendered fat(and flavor) that dripped from the beans. Combine that with the real smoke, and those were the best beans. The only thing i'll change next time is start with 3 pounds of dried beans instead of one.
2 NB Banderas, Imperial Kamado #5, Imperial Kamado #0, Large Grill Dome, Large Primo Kamado, 22.5 Weber Silver, 18.5 Weber Silver