Then, there are times like this when it becomes blatantly obvious that I have some rather large holes in my "collection." An inadequate assortment of drill bits. Not even the basic router accessories. I don't even have a drum sander.
I had thought about making overlapping holes with one of a Forstner bit, with each hole coming right up to the line of my 1.5" hole. Then clean it out with a chisel. But, my particular Forstner bits have the point in the middle, so my recess would have little divots all in it and I don't want that.
I have a couple strips of material that I have milled down to 1-3/4" wide, about 3/8" thick (a guestimate; I planed it down to what looked good). My plan was to cut the recesses 1.5" diameter and 1/8" or so deep. Then cut off 1-3/4" square pieces with the recess centered. I need 6 of those little blocks.
One alternative I thought about was taking (or making) some very thin material - about 1/8" thick or so - and making the 1.5" hole in it, then gluing it down to the 1-3/4" square block. Maybe even use a contrasting material.