along Portage Bay in the U-District. I too find it hard to find non-greasy food, and even more expensive restaurants just pile on the oil. People go there for the views and proximity to kayak rental, but I go there for the fantastic homeade Mexican food. They use the best ingredients, and is not too expensive. Their salsas are unbeatable.
Be warned, though: Agua Verde is a beautiful place to go on a nice day, so expect crowds and confusion unless you go on a rainy day.
And because most people go there regularly, the procedures for getting your food/menu/where to sit which seem normal to regulars can be confusing. The staff are very busy, but the place is filled with happy customers, so just strike up a conversation with those around you when you have questions