Sheet Pan Stir-Fried Chicken Teriyaki with Pineapple

FOR THE STIR-FRY:

boneless skinless chicken breasts, trimmed and cut into 1-inch pieces

shiitake mushrooms, wiped clean, stemmed, and quartered

large red bell pepper, sliced into ½-inch pieces

medium pineapple, trimmed, cored, and cut into 1-inch pieces

vegetable oil

minced garlic cloves, divided

grated fresh ginger, divided

salt and ground black pepper

FOR THE TERIYAKI SAUCE:

mirin

soy sauce

water

packed brown sugar

cornstarch

red pepper flakes

-ounce can sliced bamboo shoots, drained, rinsed, and patted dry

FOR SERVING:

Prepared white rice

green onions (scallions), sliced thin