Plot: Neil Patrick Harris' better half, David Burtka, is back to co-host with Rachael, and he's making his kids' favorite: Chicken Tot Pie! Then, Instagram influencer Hannah Bronfman (with over 500K followers!) is breaking down her tricks for looking younger and having more energy. (Celery juice, anyone?) And "Shark Tank's" Barbara Corcoran is answering her most-asked career questions