In a mixing bowl, combine the low-sodium soy sauce, water, brown sugar, rice vinegar, minced garlic, grated ginger, and sesame oil. Whisk until the sugar is dissolved and the mixture is well combined.
Place the salmon fillets in a shallow dish or a resealable plastic bag. Pour half of the teriyaki sauce over the salmon, making sure each fillet is well coated. Allow it to marinate for at least 15 minutes, or up to 1 hour for more intense flavor.
In a small bowl, mix the cornstarch with 1 tablespoon of water until smooth. This will help thicken the remaining teriyaki sauce for serving.
Preheat your air fryer to 400°F (200°C) for about 5 minutes. This ensures that your salmon cooks evenly and gets that beautiful golden color.
Remove the salmon from the marinade and shake off any excess. Place the salmon fillets in the air fryer basket in a single layer. Cook for 8-10 minutes, depending on the thickness of the fillets, until the salmon flakes easily with a fork and is cooked through.
While the salmon is cooking, pour the remaining teriyaki sauce into a small saucepan over medium heat. Stir in the cornstarch slurry and cook for 2-3 minutes, or until the sauce has thickened.
Once the salmon is done, carefully remove it from the air fryer. Drizzle the thickened teriyaki sauce over the salmon fillets and serve immediately. Enjoy with your choice of rice, quinoa, or steamed vegetables for a complete meal!
