"Outside" is the outside of the pork shoulder that has the bark or crust after is comes off of the bbq pit. This is where the smoke flavor is the most pronounced. A large pork shoulder coming off the pit has only a limited amount of outside on it, the rest is just cooked meat. That is why the menu states "on availability". Shoulder dinner is just the shoulder meat with no outside. Pork shoulders do not have any skin on them. Shoulder dinners are not beef, they are pork. Google "pork shoulder" to see what they look like before they go on the pit.
Outside in the skin part
I know for sure that the shoulder dinner is beef and I believe the outside dinner might be pork.
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