Tomorrow is the day! September 18th is National Cheeseburger Day, and we’re celebrating BIG at Serious Pie Ballard. Chef ET is taking over the patio flattop with his dream smashburger. @mishimareserve beef, brown butter onions, American cheese, and red eye ketchup on a bun from @rachels.bagels.and.burritos Join us 11:30am-6pm for this one-day pop-up. Come on by or Pre-order! To pre-order: choose September 18th as your pick-up date, and then claim your burger!