It's one of those “know it when you see it” types of things: a $100 Manhattan Royale crafted with rare nine-year Old Fitzgerald and the finest Bitter Queens bitters at Z Bar (108 E. Superior St., zbarchicago.com) or a handsome, sultry private alcove where you and your closest confidantes can take in the thrum of TAO Chicago (632 N. Dearborn St., taochicago.com) while snacking on decadent Asian bites. There's a little thrill folded into the very definition of extravagance, in knowing that what you're about to enjoy is deliciously, devilishly indulgent. Barton G. The Restaurant (415 N. Dearborn St., bartong.com) brought its brassy, Miami-born concept to River North earlier this year to serve up sumptuous dishes like whole branzino and lobster-and-chicken pot pie, delivered via massive sculptural platforms that test the bounds of imagination and physics. Its cocktails, too, get the royal treatment. What's even better: Each of these over-the-top destinations provides a feast for the eyes as well, from Z Bar's sweeping views of the Magnificent Mile to the scenic riverfront locale of the forthcoming RPM Seafood (317 N. Clark St., rpmrestaurants.com). This fall, the seafood-focused follow-up to the standout institutions of RPM Italian and RPM Steak will join Pizzeria Portofino and a majestic event space, offering one more fantastic way to go all out.