Thanks BluTeddi.. looks pretty much like custard pie to me. Just a switch of milk! And probably in days gone by, it was made with the "real" buttermilk and not the commercially made cultured product we get now. As for toppings, of course, I'd just go with the real whipped cream (not cool whip) and I love my custard pie made topped with fresh fruit or a stewed fruit. Or when making individual custards, I put some fruit or maple syrup in the bottom of the dish!
Love your innovative new name ... Magnolia!
And now you have me wanting to know about Vinegar Pie.
My closest would be .... Oatmeal Pie ... and no, I ever tell anyone that name either!