This started as a bit of cherry branch that a friend gave to Dad, along with a couple of smaller pieces that appear elsewhere as bowls. I tried to start the hollowing out with the Forstner bit, but went to fast and caused quite a bit of cracking. I keep it in the workshop where I can see it to remind me to take it slowly with Forstner bits and to drill progressively larger diameters. With hindsight this would have been better as two smaller, more traditional bowls, leaving out the heartwood (which is always a bit prone to cracking), but if you don't try it you will never learn.