Jessica Simpson Weight Loss After Baby: Tweets Pictures, Debuts Post-Baby Body on "Katie" (PHOTO)

Jessica Simpson flaunted her 40 lb. weight loss as a guest on the debut of ABC's new daytime talk show "Katie."

The sitdown with veteran news anchor Katie Couric is Simpson's first scheduled public appearance since she gave birth to her daughter Maxwell on May 1.

The country singer flew to New York to tape the first episode of Couric's self-titled daytime talk show.

"On my way to @katiecouric's show! I'm her very first guest - Wish me luck!! #WeightWatchers," she tweeted on Monday, Sept. 10.

After the show taping she posted, "Just finished the @KatieCouric show. So much fun! Here's my look-Roland Mouret."

Simpson wore a form-fitting black mini-dress with a flared peplum detail by Roland Mouret with black pumps.

In the interview, the fashion mogul said she had "[alot of] pressure on.. to lose the baby weight."

"Today was one of my goals: getting here, feeling comfortable. I feel beautiful today!" she added. "It definitely is a challenge. My doctors told me [my pregnancy weight] was a lot of water, and when my water broke ... All the weight did not come out with the baby. I had to stay focused on my diet. I want to be as healthy as I can because I'm a mom now." 

"I didn't really think about it. All the weight did not come off with the baby! I've had to really stay focused on my diet and really concentrate on what i'm putting in my body," Simpson said.

Simpson revealed that she has "set small goals" for herself to lose weight.

"I've lost weight every week, thank God, but I've worked really hard. I have to shoot a new season of 'Fashion Star,' " she said. 

When asked about her engagement to former NFL player Eric Johnson, Simpson admitted the couple have yet to set a date for the upcoming nuptials.

"It won't be this year. We haven't had time!" said the "Fashion Star" mentor. "I really want to do a big fun wedding with my friends and family."

Simpson signed a deal with Weight Watchers to lose her post-baby weight several weeks after she gave birth to Maxwell.