One thing we love about Michelle Obama is her confidence to wear her favorite dresses twice. And that's exactly what she did last night while congratulating the winners of the President's Dinner contest.

The first lady looked flawless in her black-and-white Tracy Reese frock with a zigzag print as she and the president dined at the Boundary Road in Washington with supporters from across the country who won the chance to dine with the Obamas.

So chic! But our favorite part? It seems POTUS donned a matching black-and-white striped tie.

Mrs. Obama previously wore this dress when she and the first lady of Britain, Samantha Cameron, served lunch for British service members and veterans in May of 2011.

It's no surprise that FLOTUS is donning Tracy Reese, as the designer has become a favorite for the first lady: she's been out multiple times in a Tracy Reese black-and-white sweater with a large bow.

Click through the slideshow to see Mrs. Obama looking casual and cool at dinner last night!

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