Notice the waistline and skirt
Sure, this model has nothing to hide, but if she did want to disguise a big tummy, this Suzi Chin Maggy Boutique Keyhole Matte Jersey Dress, $128 at Nordstrom, would help. The defined waistline should hit at a smaller area, making your middle look smaller. Additionally, the detail at the bust will detract from what's going on down below.