Season chicken with oyster sauce. Mix in egg, flour, and cornstarch.

Fry in preheated oil until golden brown. Strain and set aside.

In a pan, simmer water. Pour lemon juice, honey, sesame oil, and cornstarch mixture. Simmer until thick.

Toss in cooked chicken and cook for another minute. Transfer on a serving plate, top with sesame seeds, spring onions and lemon slices (if desired). Serve immediately.