Beyonce stunned at the Grammys ... in more ways than one!
Fans where shocked Sunday night when a scantily-clad Bey hit the stage to perform her latest hit with hubby Jay Z, "Drunk In Love."
Not only was it her super sexy dance moves that got people talking, but the singer's svelte figure was another hot topic.
"Project Runway" winner Michael Costello styled the pop star in a sheer white gown that strategically covered just her lady bits later in the night.
In new interview with E! News, the designer opens up about the dress he made for the mother-of-one ... telling E! that she's just about a size 2!
"It was incredible! We didn't have any of her sizes or measurements," Costello tells the site. "The dress was just made to fit a sample mannequin. It's smaller than a size 4. She is tiny! That dress is at least a 2/4. She looks amazing. I just love the way it all came together. Ty [Beyonce's stylist] knew it was going to fit."
The 32-year-old definitely looked the skinniest we've ever seen her!
While Michael was worried about the size, Bey's stylist new the dress would fit. "At first I was a little concerned with the pieces I gave. Maybe it needs to be smaller or bigger? When you send something to Beyonce, you're just a little concerned, but Ty knew. Ty knew the fit," he says.
And Ty didn't even schedule a fitting until the day of the Grammys, either!
"The neckline, the back, the hemline was not complete, and we still had to do some of the hand sewing on it," he says. "We put in a good extra day's work. We had a great team. I made four other pieces that night for Beyonce, so that Ty had good options."
Mrs. Carter looked amazing in her Winter white ensemble, and Costello was just as pleased with the way the dress turned out.
"When I found the fabric and cut out the leaves and flowers. It all came out together magically. I remember sketching out the dress, and I thought this is exactly how I wanted to do the dress."
Beyonce definitely had all eyes on her during the major night in music -- are you surprised about the singer's small size? Tell toofab in the comment section below, and click "Launch Gallery" above to see even more photos from her performance!