No surprise at all that Park Avenue Summer feels so summery—shiny white panels glowing, tall reeds and grasses dividing the room in a smart AvroKO design. Chef Craig Koketsu’s kitchen tunic is never-before-seen seersucker. The pleasant surprise is how good his food is: Subtle peekytoe crab has gregarious mates in silken avocado and a potent gazpacho julienne. Tired old caprese is born again inside ravioli with a scintillating yellow-tomato coulis. Soft-shell crab couldn’t be crisper, with strawberry balanced against passion fruit, white soy, and avocado, an unlikely gathering that works. Here comes avocado again with fennel in a citrus vinaigrette shoring up exquisitely cooked lobster. Alas, the John Dory is overcooked, though I’m wild for the brioche-crusted poached egg with summer truffles, and the excellent lamb chops. Adventurous cocktail fans will love the do-it-yourself bar with fresh-squeezed juices and pile-ons stashed in drifts of ice. I doubt Upper East Siders will be put off by high-priced starters and entrées up to $45 with food this delicious. But some training would help. Managers cringe as runners and busboys run amok. I worry about a waiter who touches and the maître d’ who urges us to “Enjoy. Okay?” Soon enough, walls, snap-on seat covers, flowers, and menus, of course, will morph into Park Avenue Autumn. “Do you think it will work?” Alan Stillman asks of his son Michael’s homage to Joe Baum’s Four Seasons. Why not?