I use two different methods to yield super tender, juicy chicken strips. First is to cut chicken breasts against the grain. Don't just cut the chicken any way you like- notice where the grain lines are and be sure to cut opposite them. This makes the cooked fibers of the chicken shorter, so they tear apart easier. Cut strips as big or small as you'd like, just cut against the grain! The second method is to add cornstarch to the chicken marinade. I first noticed asian recipes calling for cornstarch in the marinade. When I researched it, it turns out adding cornstarch to chicken prior to cooking it gives it a protective coating that locks in juices. It works so well!