Cook rice according to the instructions on the packet.
Clean the baby pak choi and remove the roots and leaf stalks. Cut the spring onion diagonally into rings and slice the garlic thinly.
Heat a wok or large pan over medium-high heat with 1 tablespoon of peanut oil. Fry the peanuts for 1-2 minutes until golden, then drain on paper towels.
Add the remaining peanut oil to the wok and increase heat to high. Sear the chicken fillets in batches for 2-3 minutes until browned. Remove and set aside.
Fry the spring onion and garlic in the same wok over high heat for 30 seconds.
Return the chicken, add the baby pak choi, water, and hoisin sauce. Cook over high heat for 2-3 minutes, stirring constantly, until the pak choi is dark green and the chicken reaches 74°C / 165°F.