Downtown Issaquah is small enough that you can walk every restaurant in twenty minutes. The mix is suburban-American with a few local highlights: solid Northwest breakfast spots, Mexican places, a famous burger joint, and good independent coffee.
XXX Root Beer, a 1960s drive-in by the salmon hatchery, is a local institution — order the bacon cheeseburger and a frosty mug of house-made root beer. For Korean, JaK's Grill has good steaks and Sip Wine Bar covers wine flights and small plates if you want something more polished.