Cut the salmon crosswise into four slices. Finely chop the inside of the lemongrass, finely chop the ginger, mix with the oil and pepper. Brush the salmon with the mixture, cover and leave to marinate in the fridge for approx. 1 hr. Season the salmon with salt.
Cut the leeks into strips approx. 4 cm long, quarter the pepper and cut into strips. Place a steaming basket into a wide pan, fill with water until it is just below the bottom of the basket, bring to the boil and reduce the heat. Add the leek and pepper, season with salt. Cover and cook on a medium heat for approx. 10 mins.
Place the salmon pieces on the vegetables, cook for about another 15 mins. Plate up the vegetables, drizzle with a little soy sauce. Serve topped with the salmon pieces.
Serving suggestion: Rice.