While not the same as ordering from the menu in the main dining room, the buffets on Carnival are actually pretty good. There's a pizza station, a New York style deli (on most ships) that has really good sandwiches, lots of fresh fruit, a hot buffet that has typical breakfast items (as Trip mentioned), for lunch and dinner there's usually cheeseburgers, fries, sometimes chicken, fish, veggies, and a salad bar. And plenty of desert items. After you've arrived at the port and gone through the embarkation process, head up to the Lido deck and check it out. Even if you're not real hungry, you can get coffee, iced tea, fruit punch, juice, or ice water. And there's always room for a little dish of soft-serve ice cream
. If one of the tables out near the pool area are available, it's a great place to sit and people-watch. By the way, if you take your own travel mug with you, you can save trips to the beverage station.