My fashion idol is Audrey Hepburn. That always seems to shock people, as though a 220-pound Cuban spark plug like me couldn't possibly emulate the grace and style of Hollywood's doe-eyed, pocket-size beauty. In fact, Hepburn has inspired much of my wardrobe—the little black dresses, crisp white button-downs, pretty ballet flats. These looks are flattering and chic, no matter what your size. So when a frustrated, full-figured shopper asks me for shopping tips, I always advise her to start with the classics. I recently ransacked my closet and compiled a list of my all-time favorites, the cornerstones of virtually every outfit I wear. I'd sooner part with my kid brother than any one of them. (Kidding, I swear.)

Little black dress. I confess: I own a dozen, each so versatile it could take me from a frenetic afternoon styling a six-page fashion story to a paparazzi-packed movie premiere hours later. Because big girls can't "wing it" like our willowy friends (there's no such thing as running to the mall after work for a last-minute sparkly number when you're a size 18), my frocks must be flexible workhorses that see me through day to night. My current fave is an Ann Taylor sleeveless sheath with flirty ruffles that's fitted at the waist. Take note: Shapeless shifts make better drapes than dresses.

White button-down. I spent much of my life avoiding this wardrobe classic like a nasty cold. My beef: I needed a wrench to get the shirt buttoned over my ample chest. I've resorted to safety pins, double-stick tape, even sewing myself in just to keep it closed. It wasn't until I came upon a form-fitting yet roomy Ralph Lauren button-down in a thick oxford cotton that I finally got over my aversion. I wear my button-down under blazers or on its own, and dry-clean it often, as though it were a gift from Ralph himself.

Black pencil skirt. Look for one with a lining (to reduce cling) and made, in part, of spandex, like the skirt I snagged from New York & Company a few years back. I'm wearing the poor thing to death, to both casual dinners and formal work events. The lesson: If you find an item you adore, buy two of them.

Trenchcoat. While I don't have much use for a trench in sultry Miami, my hometown, I prefer to wear one on my frequent trips to New York City. Even if I'm dressed down in jeans and a shabby shirt, the addition of a well-tailored trench instantly quadruples the sophistication level. I like the Deborah double-breasted trench from London Fog, which elongates my barely 5-foot frame. The company offers a range of jackets in plus-sizes—definitely worth checking out.

Have I missed something? Tell me what wardrobe classic you can't live without—and where you got it.

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