Contrary to popular belief, Spam is already cooked before it’s packaged, and it is completely safe to eat straight out of the can. While uncooked Spam might not have the most desirable texture, it does work great for camping or other situations where cooking might be difficult.
Spam's "best by" date is generally about three years from when it was manufactured, so, provided the can hasn't been damaged or opened in any way, a can of Spam will keep for a long time. Once opened, Spam should last sealed, in the refrigerator, for around seven to 10 days.
Spam is not a typical cold cut and, therefore, it should not be sliced as thin. To keep other ingredients from overpowering its taste, slice your Spam about a quarter-inch thick. This works great in Spam musubi — the Spam-meets-sushi snack that's become a staple of Hawaiian cuisine — and in a sandwich.