All the crockpot recipes I've used add a can of evapmilk but no regualr
milk........no need to thin it.......I would guess it could sub 1 to 1,
but I'm pretty new to the whole crockpot thing.

I've got a great recipe for a crockpot mac & cheese that turns out like
baked mac & cheese casserole. It uses 1 can of evap milk along with the
butter, cheese, and a couple eggs. I've made a creamy broccolo soup
with sauteed onions, chopped broccolie, stock, and a can of milk, plus
some shredded cheese, basically. Seems like a 1 to 1 replacement from
those 2 I've done.