I'll second King's Fish House. You can tell the fish is fresh and they're a bit more inventive with the vegetables when compared to Fish House Vera Cruz in downtown Carlsbad. I like both places, but King's is right there.
If you go down to Encinitas, I've heard La Bonne Bouffe is good. I haven't been able to get a reservation yet, but one of these days...
King's Fish House (across the street from the outlets) is alright, but I think you've got that in the OC, too.
I've had a good meal at Vigilucci's on State St. in downtown Carlsbad (exit I-5 at Carlsbad Village Drive). Here's their site:
The outlets aren't far from Encinitas. A search for "Encinitas" would turn up quite a few hits on this board.