Adze
Using an adze is a great way to quickly and efficiently remove material from bowls, kuksas and even spoons. By striking the pole (the back) of an adze with a mallet or maul you can have excellent accuracy and the sweep of the adze will cause it to follow its curve and round out the material it is removing.
Having an adze in your kit is a really valuable tool that will save you loads of time and is also enjoyable to use.