Yeah, I'd say OTC burleys make for a fine cake. Like Cater Hall and Prince Albert. But really when it comes down to it, just smoke what your favorite brand is and sure enough you'll develop a fine cake. Say, after ten bowls or so, you'll see it developing nicely. When I break in a new pipe I will intentionally give it less attention to cleaning out the bowl, as compared to other pipes with a well developed cake. After I smoke down to the bottom (I don't do thirds, just load her up and go), I'll shake the ash up in the depleted bowl to coat the chamber walls evenly. Clean the draft well. Then rack it. I'll do this for the first half dozen bowls or so. Then I'll begin to give attention to the chamber, by gently swabbing it with a used bent pipe cleaner. After another half dozen bowls or so, then I'll get more aggressive with the chamber and begin wiping it out with a twisted paper towel. Once the cake is nice and good, why, I'll dribble some drops of alcohol into the chamber and insert a bit of paper towel and using a pair of forceps twist it around to REALLY clean out the bowl. Your millage may vary, depending on how retentive your anus is.