So my assumtion (and I hate the word "assume"
) that a chestnut is a chestnut is obviously wrong. Don't know if the tree these came off of is "wild" or not. Or even if they are horse chestnuts. It's a tree in someone's back yard and the nuts drop all over the place outside of their yard (I don't know the people) and I picked them up.
I did find out, however, that they need to be "cured." And curing them is nothing but letting them dry out and that sweetens up the meat. That can take a week or three, and since these nuts are super fresh (some were even dropping off the tree as I was gathering them up), I imagine it'll take a few weeks.