When you walk into the Alexandria, the new bio-tech center building on the banks of the East River, you are confronted by a sign: Riverpark, a Tom Colicchio restaurant. But if you go on to have a couple of very fine meals there—as we did—it is highly unlkely that you will find Mr. Colicchio there. It's chef-partner Sisha Ortuzar running the kitchen. When pressed for a pithy description of the menu at Riverpark, Ortuzar said it was American food with a New York point of view. When pressed on whether the restaurant lacked focus, he said with a giggle, "It is all over the place in a controlled manner." And that's about right. More