Combine the white and black chia seeds on a plate. Press each salmon fillet in the chia seeds to evenly coat one side, then set aside.

Remove the stems from the choy sum, cut in half if long and reserve. To make the tamari dressing, put all the ingredients in a small bowl and stir to dissolve the sugar.

Heat 1 tablespoon of the oil in a large nonstick skillet over high heat. Cook the salmon, chia side down, for 2?3 minutes (or until golden). Turn and cook for a further 2 minutes (for medium) or until cooked to your liking. Set aside and keep warm.

Meanwhile, heat the remaining oil in a large wok or skillet over high heat. Add the ginger and garlic and stir-fry for 30 seconds. Add the choy sum stems and stir-fry for 1?2 minutes, then add the choy sum leaves and stir-fry for 1 minute more or until almost wilted. Add half the dressing and toss to combine.

To serve, divide the choy sum among serving plates, top each with a piece of salmon and drizzle over a little of the remaining dressing. Serve with noodles or steamed rice.