I have made a cutting board vaguely similar to the one Bill Tindall made. His was square, mine is round and turned on a lathe.
I turned mine with it mounted at and angle so the depression slopes from nothing on one side to about a 1/2" deep on the other. The board is 15" in diameter. The question is, Is that enough?
I'm thinking I need to put it back on the lathe and increase it to 3/4" of slope and maybe have a rim or maybe an 1/8" on the shallow side.
Second question. Why have it slope to one end? It would be easier to just turn a depression into the center. Maybe having the food sit in its own juices would not be appetizing.