A moderated usability test
The drama becomes high when Participant no. 2 is given the task of ordering a combo pizza—one with two toppings, half and half—on an unfamiliar site. Along the way, she changes her mind about what she wants and has to edit one of those toppings. Will she make it to the cart and get to the Submit button? (Spoiler warning: she does.)
The following video is a 10 minute except from the 27-minute usability walk-through.