If at first you don't see Icing On The Cake in the block of storefronts at 230 Adams St., just follow the aroma of freshly baked cakes. Despite being almost hidden in the corner, people have no trouble finding them. It's been in business for more than 25 years and the kitchen is constantly busy. Keeping several bakers working, owner Paula Kirrane and family specialize in wedding and special event cakes.