Forget the sheepish funk of the esteemed Keens Steakhouse mutton, it’s the midtown chophouse’s monster porterhouse that you want to order when you’re not picking up the tab, its dry-aged pink peeking through melted fat. Start with a seafood tray? Don’t mind if you do. No harm hinting that your table needs another plate of bacon and hash browns, either. And open another bottle of wine while you’re at it. After all, when you navigate your way through the restaurant’s maze of 19th-century pipe-domed parlor rooms, it won’t be your wallet that’s empty.