In a small bowl, mix oyster sauce, soy sauce, honey, garlic, and lemon juice. Stir until combined.
Season the chicken with salt. Heat a large pan over medium heat, add a drizzle of oil, and place the chicken in the pan. Cook until golden on both sides. Remove and set aside.
In the same pan, add butter and let it melt. Sauté the onion until softened, then pour in the prepared sauce. Cook for 2-3 minutes until the sauce thickens slightly.
Return the chicken to the pan, coating it in the sauce. Simmer for a few minutes until the chicken is fully cooked and glazed.
Serve the chicken over steamed rice. Slice the chicken into strips, then garnish with chopped green onions and sesame seeds. Serve immediately.