The Mickey-shaped butter they used to serve!
(Not that I ate that by itself!

)
I totally agree. I loved that!
I also agree with the Beaver Tails in Canada, chowder in bread bowl at CHH, handwiches and Casey's original hot dogs.
Here are some more:
Spoodles- I miss the restaurant in general. I loved the yogurt marinated chicken from eons ago as well as the more recent Spoodles Sangria and the Lemon Garlic shrimp. When they first introduced that dish (maybe 05? 06?) it was awesome. By the closing of Spoodles it was NOT the same recipe. Rigatoni Fiesolana and the Italian Breakfast were awesome, too.
'Ohana- I miss the menu I had when I first dined there, but my most missed dish is the 'Ohana green beans- fresh green beans blistered in a bit of hot oil with red onion, crisp bacon and a sweetened soy glaze. I have made that at home many times.
Boardwalk Bakery- Cinnamon Yummies
Main Street Bakery- French Toast Loaf
Prime Time Cafe- Grasshopper Shake (creme de menthe and chocolate adult shake)
Wonders of Life- Chocolate Low Fat Frozen Yogurt Shake
Snack- Goofy Ice Cream bar (caramel and nuts)
I may update if I think of more!