So I was trying to do the Turkey Easter egg and input the wrong code. Instead of the turkey gaining a hood a chest popped up on the mini map. The chest was behind the stable on a ledge over the cliff. Since this was a mistake, I'm not sure if the chest was always there and it unlocked the location on the map or if it spawned the chest. I do know that the chest wasn't on the map before. When opening the chest I got the messages:
"New upgrade available" & "New Recipe Available"
Again, I'm not completely sure what was actually unlocked.
Here is what I did, while the turkey was following me I entered one of the following:
Up, Down, Up, Down, Left, Right, Left, Right, A, B
Up, Up, Down, Down, Left, Right, Left, Right, A, B
I'm fairly certain it was the first.