I'm not expert cook, so take this for what it's worth...
I have basically three favorite ways I like to eat moose heart.
1.) In hunting camp, cut up into thick steaks and fried in oil, green peppers, onions, and a little salt and pepper. Basic, but a great camp dinner.
2.) Done in a crock pot with your favorite roast recipe. I like ones with potatoes, carrots, onions, and lots of gravy... but I'm a simple kinda of a guy.
3.) Cut into 3/4" steaks and barbeque on a charcoal grill. As a twist, I like to eat these on a hamburger bun with cheese and the fixin's . The tender texture lets you eat it like a burger.
I've got a moose heart in the freezer myself I'm looking forward too.
Yk