Cut skirt steak into individual strips.

Combine teriyaki sauce and garlic in a bowl; transfer to a resealable plastic bag. Add steak strips, coat with marinade, squeeze out excess air, and seal the bag. Marinate in the refrigerator 8 hours to overnight.

Set an oven rack about 6 inches from the heat source and preheat the oven's broiler (or preheat an outdoor grill and lightly oil the grate).

Remove steak strips from marinade and shake off excess. Discard remaining marinade.

Place meat on a broiler pan (or directly on the grill). Cook to desired doneness, about 5 minutes per side.