First, remember that the carbide bit is fragile.   If dropped, it will likely break and therefore it is always a good idea to have a spare bit on hand.
 
Make a series of light cuts, about 1/16” or 3/32” per pass, clearing the chips along the way until the desired depth is achieved, the edges are true and the recessed surface is flat.
 
We recommend a final depth of about 3/16” or slightly less.  Note that the patch thickness is just over 3/16”, about 0.2”.