Preheat the oven to 425°F (215°C). Place an oven-safe baking rack on a rimmed baking sheet and lightly spray the rack with cooking spray.
Trim any visible fat or tendons from 1 pound chicken tenderloins. If using breasts, cut into 1-inch-wide strips.
Set up a breading station with three shallow dishes: combine 1 cup all-purpose flour with 1 teaspoon seasoned salt in the first; whisk 3 large eggs with 1/4 cup water and 1/2 teaspoon seasoned salt in the second; place 2 cups plain panko with 1 teaspoon seasoned salt in the third.
Dredge each chicken strip in the seasoned flour, shaking off excess, then dip into the egg wash, letting excess drip off, and press into the panko to coat evenly.
Arrange the breaded chicken tenders on the prepared rack. Lightly spray the tops of the tenders with additional cooking spray to promote browning.
Bake in the preheated oven for 10–13 minutes, or until an instant-read thermometer inserted into the thickest part registers 165°F (74°C); no flip is needed when using a rack.
Remove from the oven and let rest for 1–2 minutes before serving.