I started with a birch log (a gift from Gilbert Rivera):
Mounted the blank with the wormwood screw turned the outside and cut a tenon on the bottom.
Then I mounted the bowl on the 4 jaw chuck to turn out the inside.
And used the live center tail piece to stabilize it.
then I turned off the inside tenon and in the process, accidentally broke off the foot tenon (in the 4 jaw chuck).
So I glued it back on with CA glue and
tried turning it again sometime later and broke off the tenon again. So, I reverse mounted it in the Cole Jaw chuck and turned a recess in the bottom to hold it in the expansion chuck.
Final result, after thinning the walls and turning down the top edge and adding some detail (finished with beeswax, carnuba wax and mineral oil):
(9 1/4″ x 4 1/2″; biggest bowl so far)
Bottom view showing the recessed bottom.