My bowls are finished with multiple coats of a drying varnish which, after the curing time, is food safe. The bowl is then buffed and coated with carnauba wax.
Never put it in a dishwasher, as this subjects the finish to high temperatures and strong detergents that will significantly damage the finish.
To clean, in most cases a wipe with a soft damp cloth is enough. In special situations, hand soap on a soft cloth can be used, followed with a damp soft cloth, and soft drying cloth.
Over time, you may find that the finish seems dull. If this happens, just recoat the bowl with a good wax and buff with a soft cloth. Also, salad bowl conditioner from the Holland Bowl Mill in Holland, MI, is a product I have used for this purpose.
