Egg-based dish (8)
'egg-based dish' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for omelette that I've seen before include "Dish of fried beaten eggs" , "One getting beaten" , "Dish of cooked beaten eggs" , "Smashed eggs" , "breakfast" .)
(Other definitions for souffle that I've seen before include "Light fluffy dish with a base of egg yolks and stiffly beaten egg whites" , "Very light baked dish" , "Low murmur" , "Dish made of egg yolks and stiffly beaten egg whites" , "light baking" .)