01 - Preheat oven to 400°F (200°C). Line a baking tray with parchment paper or lightly oil it.
02 - In a small saucepan, combine soy sauce, mirin, honey, brown sugar, rice vinegar, minced garlic, grated ginger, and sesame oil. Bring to a gentle simmer over medium heat, stirring until sugar dissolves and the mixture slightly thickens, about 3–4 minutes. Remove from heat and allow to cool for 2 minutes.
03 - Place salmon fillets on the prepared baking tray. Brush half of the teriyaki sauce generously over the fillets to coat evenly.
04 - Bake in the center of the oven for 12–15 minutes or until salmon is opaque and flakes easily with a fork.
05 - Brush remaining teriyaki sauce over the cooked salmon. Scatter sesame seeds and sliced spring onions on top before serving.