Breakfast is included with the all-day dining. Only one restaurant serves breakfast each day. You will want to check the park map when you arrive to see where it is on your particular visit day. When we were last there in December 2012, breakfast was offered at Voyageurs Smokehouse.
I know they had french toast sticks, eggs, homefries, breakfast meats (different platters offered various combinations, and the meats were bacon, sausage, and also ham too I think), gigantic muffins, fruit, and I'm sure there was also more. Standard breakfast fare, but not buffet style.
During the holidays when we went it was at seafire. So like Gina said be sure to check the map it will have it listed on the back. We always get there at opening and grab some breakfast while we look at show times and plan out part of our day.