Once the tea bags have infused for 5 minutes, discard the bags. Stir in the ginger, garlic, kecap manis, sweet chilli sauce and honey until well blended. Leave to cool.
Lay the trout fillets in a shallow glass or ceramic dish and pour over the tea mixture. Cover and leave to marinate in the refrigerator for at least 4 hours, or overnight if time permits, turning the fish occasionally.
Remove the fish, reserving the marinade, and pat dry on kitchen paper. Heat the sesame oil with 1 tablespoon of the groundnut oil in a large nonstick frying pan, add the fish, skin-side down, and cook for 2–3 minutes. Turn the fish over and cook for 3 minutes. Remove to a warmed plate and cover with foil – it will continue cooking in its own steam while you cook the pak choi.
Heat the remaining oil in the pan over a high heat, add the pak choi and stir-fry until just beginning to wilt. Pour in half the reserved marinade, bring to the boil and cook for 3–4 minutes until most of the liquid has evaporated and the pak choi is tender. Serve with the trout.