To make the marinade, add the avocado oil, tamari, apple cider vinegar, sesame oil, brown sugar, garlic, ginger, sesame seeds, and crushed red pepper flakes to a bowl, then whisk to combine.
Place the salmon fillets into a sealable storage container or large bowl, then pour the marinade over the salmon filets. Allow the salmon to marinate for 1 hour or refrigerate overnight in a sealed container.
Preheat your oven to 400 degrees Fahrenheit and line a rimmed baking sheet with parchment paper or foil. If using foil, spray with non-stick cooking spray.
Place the marinated salmon fillets onto the prepared sheet pan and bake for 15 - 20 minutes, depending on the thickness of your fillets. It should flake easily with a fork.
While the salmon is in the oven, make the sesame glaze. Add the brown sugar, tamari, sesame oil, sriracha, ginger, and sesame seeds to a small bowl, then whisk to combine.
Once the salmon has finished baking, spoon the glaze over the salmon, garnish with green onions if desired, and serve immediately. Enjoy!