So, normally, I'm not much for cooking meat in oil or fat, but i was going for a confit lie texture. The heart was in iffy shape, already butchered, so most of my landmarks for butchering it were gone. It doesn't look very pretty, hence the lack of photographs.
Anyway, lightly salted the pieces, tossed them in the bag with a healthy amount of tallow. Cooked at 132°F for 48 hours.
Even my significant other, who is a very very not adventurous eater, had to admit it was good. Granted, our son had to eat a piece first, but my guy will eat most things i give to him.