Preheat oven to hot. Combine chicken pieces, lemon grass, spring onion, fish sauce, sambal oelek, sugar and peanut oil in a large bowl and mix well to coat. Transfer chicken pieces to a pre-heated lightly oiled baking dish. Bake uncovered, in hot oven for about 15 minutes or until chicken is cooked through.
Meanwhile, fry sliced onion in oil for a few seconds. Add bok choy and bean shoots, stir gently. Cover and cook for approximately 3 minutes.
Place in a serving dish and drizzle with warmed sesame oil and oyster sauce. Place chicken on top of vegetable and bean shoot mix and serve.