I find that most meals on property are pretty huge. Hubby and I almost always split meals (including counterservice) or I often get a kids meal for counter service. I have noticed that the kids meals this past trip were much smaller (probably because of the low cost of kids on the dining plan).
But what you are looking for depends on counter service or table service. Any combo meal at counter service (particularly the chicken and rib combos) are pretty darn big. There are also double bacon cheese burgers at counter service that are huge. These are pretty standard items at some restaurant in each park.
50's Prime Time Cafe in Hollywood studios has about the biggest portions I think i've ever seen.
For your best value try the buffets. We like trails end at the Fort Wilderness Campground. It has the same food as the hoop dee doo show and only costs 20 bucks for adults for dinner (less for lunch)...lots of ribs, chicken, salmon, shrimp, cornbread, soups, salad, desserts...uggg I feel full thinking of it!.
The Wilderness Lodge also has an all you can eat BBQ skillet with brisket, corn, beans, ribs, chicken, cornbread but I think it is more than the buffet at Trails end, about $24. But it also is a fun place and has a regular menu you can order ala cart. They also have bottomless milkshakes and you can try every flavor if you want.
Polynesian Captain Cook's counterservice BBQ pulled pork sandwich with aloha chips is a lot of food!
Port Orleans French Quarter Counter-service has a lot of options. We just split a chicken quesadilla meal. It was huge and had rice and beans and they add extra lettuce, cheese, tomatoes, sour cream and quacamole for free if you ask. Hubby and I could barely finish it splitting it. They also have a huge muffaletta sandwich with pasta salad. Definite share meal as well.
Wolfgang pucks express in Downtown Disney has huge portions and good prices and is a counter service credit. EASY to split meals there.
Rainforest Cafe and T-rex both have huge portions. They are pricey but you definitey have MORE than enough to share and have leftovers. They are not on the dining plan.
For huge snacks try goofy's candy company at DTD for a make your own treat. Huge!
Or i've seen a lot of chatter about the Dinoland and Mainstreet bakery ice cream sandwiches. (2 HUGE cookies with 3 scoops of ice cream) or the Mainstreet bakery cinnamon rolls that are as big as your hand.
I have not met many Disney restaurants where I felt the meals were small. Allears.net has a complete list of menus and prices. One thing is certain, nobody ever goes hungry at Disney.
