Unfortunately, exquisite food is not Efteling's strong point. The park excels in snack food though, with lots of places to buy fries or pizza. Try the typical Dutch fries with Mayonaise at the Smulpaap in Marerijk. Also available are the Dutch "snack wall" vending machines that give you a warm snack when money is inserted.
Apart from snacks, there's two self-service restaurants: Witte Paard white horse in Marerijk and De Ballonvaarder in Reizenrijk. Next to the latter is also a waited restaurant Welkom, and one in the theatre near the entrance. There serve relatively simple dishes and special children's menus.
Recommended is Het Poffertje across the Caroussel palace. Here you can eat authentic Dutch poffertjes -- very small pancakes served with butter and sugar.
In contrast to many other theme parks, bringing your own food is perfectly allowed. Although smoking is allowed in open air, tobacco is not sold inside the park.