I cook mine the same or next day over a hot mesquite fired grill. Great eating. Cut off the top with the arteries and discard and just thinly slice it with salt and pepper. Its good just like that as a snack or in a corn tortilla with pico de gallo.
I got a little more specific info from Youtube. I've cut out the arteries and valves. Thinly sliced them and put salt, pepper, and garlic powder on them.
Damnit wanted to save the hearts but failed to do so. Two more tags left this year. Will definitely do it on one or both, as long as the hearts survive.