I dont add any dressing to mine, havent got that bored of the foods yet so Im hanging off the dressings till I feel the need for a change in flavour. I do add chilli powder and herbs to my chicken dishes though to give it a bit of a kick.
I know other 790'ers add low fat dressings as long as it doesnt have citric acid in, its the ones from Sainsburys if I recall? Im sure one of them will be along soon and clarify? I tried finding a thread that was discussing dressings but cant find it for you?