She's back and better than ever!

Jessica Simpson shows off her impressive post-baby weight loss in a series of little black dresses for the new Weight Watchers commercial, which aired for the first time Monday night, and we don't think they could have chosen a better spokeswoman for the brand!

"This body made two amazing little human beings. I love this body and what it's capable of. No matter what size, but this version feels really good," she says in the ad.

The fashion mogul signed on to be the face of the new campaign when she was pregnant with her first child Maxwell in 2012, but when she discovered she was pregnant again with son Ace, her deal was put on hold until after his June 2013 birth.

Considering the blonde beauty is engaged and set to walk down the aisle this year, she's probably got a little extra motivation to stay in shape!