Mix the teriyaki sauce ingredients together, making sure to mix in the brown sugar that will settle to the bottom. Pour the marinade over your salmon in a small, shallow bowl and then cover and marinade for at least 30 minutes but up to 2 hours. Make sure to reserve 1 cup of the marinade to top the salmon with.
Add parchment paper to the bottom of your air fryer, making sure it fits well as to not block air flow. Cook the salmon in the air fryer at 370 degrees Fahrenheit for 11-15 minutes. The size of your fillets will determine how long it needs to fully cook through. The inside temperature should be 125 to 130 degrees Fahrenheit.
While the salmon is in the air fryer pour the remaining marinade into a small saucepan and bring it up to a very gentle simmer and then add the cornstarch slurry. Mix well for a couple of minutes until it has thickened. If you want it thicker, you can add another cornstarch slurry (see instructions in the post above).
Serve the salmon with your choice of rice or vegetable and top with the thickened teriyaki sauce.