Nicole Chavez / Instagram 1 / 5
Nicole Chavez / Instagram 1 / 5

She's officially back! Jessica Simpson has debuted her official post-baby beach body via Twitter. The 33-year-old singer retweeted a sexy photograph of herself wearing a one-piece white bathing suit while gearing up to shoot ads for her Jessica Simpson Collection on Friday, Nov. 15.

PHOTOS: Jessica through the years

"Guess which mama I get to play dress up with today?" her stylist Nicole Chavez wrote. Shortly after, Simpson retweeted the photo and added: ";) @JSCollection."

PHOTOS: Jessica's family album

In the hazy photo, the former Fashion Star mentor shows off her svelte physique while sitting outside poolside in a cleavage-baring suit. She's also seen arching her back while placing her right hand on top of concrete surrounding the water, with her blonde locks down and swept to the right side concealing her face.

PHOTOS: Jessica's second pregnancy

The mom of daughter Maxwell, 19 months and son Ace, 5 months, has been working out since giving birth to her baby boy in June. One week earlier, she shared a picture of herself while working with Weight Watchers.

"Couldn't stop smiling on set for my new @weightwatchers campaign today! #happy," she wrote on Nov. 8. In the photo, Simpson dressed in tight-fitting jeans and a white button up for the shoot. The program previously helped her drop 70 pounds after giving birth to Maxwell in May 2012.

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Better with or without makeup?