Really nice looking bowl... one of my favorite woods is Hackberry... I just scored a couple of logs and am working on a bowl now... hope it turns out as nice as yours.
The logs I have are a little wet yet, they've been cut a while, but have laid in a pile of wood for a few months in the rain... the one I turned today was at 44% moisture when I finished it... I spun it for a while while washing inside with mineral spirits... the mineral spirits slung through the wood, after it spun at 2000 rpms for a bit, put it in the microwave for 3 sessions at 3 minutes each and got the moisture down to about 15%... left it sitting in the shop overnight and will check it again tomorrow to see if it dried more overnight... may have to run it through the MW again tomorrow so I can sand and finish it.