During the holidays, you can find the adorable gingerbread men with mouse ears cookies. They are sold at most of the candy shops and bakeries, but they are exclusive to that time of year. They are pretty hefty cookies, too - not flimsy at all.
Of course, these are not particularly unique, but you can only find the Mickey Mouse full size pancakes at the River Belle Terrace and the full size MM waffles at Carnation Cafe. (Smaller versions of the pancakes and waffles can be found at character meals..)
Oh! The PCH Grill in the PPH has that decadent, sinful, artery-clogging "Kitchen Sink" dessert, which has like 8 or 10 scoops of ice cream, every topping you could ever imagine, as well as brownies, candy bars and all kinds of stuff thrown in it - it is ENORMOUS!
Goofy's Kitchen used to serve creme brulee French toast, but apparently that has been removed from their buffet offerings....however, they do offer Mickey-shaped cobbler!!