Preheat and prep: Heat your oven to 400°F (200°C). Line a baking sheet with foil or parchment for easy cleanup. Lightly oil the surface.
Mix the teriyaki sauce base: In a small saucepan, whisk together the soy sauce, honey, rice vinegar, sesame oil, garlic, and ginger.
Bring to a gentle simmer over medium heat.
Thicken the sauce: Stir the cornstarch with cold water until smooth. Slowly whisk this slurry into the simmering sauce. Cook 1–2 minutes, stirring, until the sauce is glossy and slightly thick.
Remove from heat.
Prepare the salmon: Pat the salmon dry and place it on the prepared baking sheet, skin-side down if using skin-on fillets. Spoon about half of the teriyaki sauce over the top of the salmon, coating evenly.
Bake: Bake for 10–12 minutes, depending on thickness. As a guide, 1-inch thick fillets take around 12 minutes.
The salmon should flake easily and be just opaque in the center.
Optional broil for glaze: For a stickier, caramelized finish, switch to broil for 1–2 minutes. Keep a close eye on it so the sugars don’t burn.
Glaze and garnish: Brush the salmon with some of the remaining sauce. Sprinkle with sesame seeds and green onions.
Serve with extra sauce on the side.
Serve: Plate with steamed rice, sautéed bok choy, broccoli, or a simple cucumber salad. Add a squeeze of citrus if you like a bright finish.