Prepare the Teriyaki Base. In a small mixing bowl, whisk together the sauce ingredients. Continue whisking until the cornstarch is fully dissolved and no lumps remain.
Marinate the Salmon Cubes. Slice the salmon fillets into uniform 1-inch cubes. Place the cubes in a shallow dish and pour half of the prepared sauce over them. Toss gently to coat and allow the fish to marinate at room temperature for 10 minutes. Reserve the remaining sauce for later.
Prepare the Vegetables. While the fish marinates, wash and prep your produce. Break the broccoli into bite-sized florets, thinly slice the bell peppers, and julienne the carrots into matchsticks.
Flash-Fry the Vegetables. Heat one tablespoon of oil in a large skillet or wok over medium-high heat. Add the broccoli, peppers, and carrots. Sauté for 4–5 minutes, stirring constantly until the vegetables are vibrant and crisp-tender. Transfer the vegetables to a clean plate and set aside.
Sear the Salmon. Wipe the skillet clean and add a fresh drizzle of oil. Once the pan is shimmering hot, add the salmon cubes in a single layer, ensuring they do not touch. Sear undisturbed for 2–3 minutes to develop a golden-brown crust. Flip the cubes and cook for an additional 1–2 minutes until nearly cooked through.
Reduce the Glaze. Pour the reserved portion of the teriyaki sauce into the skillet with the salmon. Allow the liquid to come to a simmer and bubble for 30–60 seconds. The sauce will darken and thicken into a glossy glaze that clings to the fish.
Incorporate and Heat Through. Return the sautéed vegetables to the skillet. Use a rubber spatula to gently fold the ingredients together, ensuring everything is evenly coated in the glaze. Heat for 60 seconds until the vegetables are warmed through.
Garnish and Plate. Remove from heat immediately to prevent overcooking. Garnish with a sprinkle of sesame seeds and sliced green onions. Serve warm over a bed of jasmine rice or rice noodles.