In a large fry pan, add brown sugar and 1 cup of water and cook over medium high heat, stirring occasionally until it starts to boil.
Reduce heat, stop stirring and let it simmer for about 2 – 3 minutes, watching carefully until the caramel starts to thicken.
Remove from heat, add the garlic, ginger, fish sauce, chilli, olive oil and vinegar and set aside while you cook the trout.
In a separate fry pan, heat vegetable oil over high heat and add trout cutlets. Cook first side for 4 minutes or until a golden crust develops. Flip cutlets and repeat. Remove from heat.
Return caramelised fish sauce to the heat, add ¼ cup of water if it’s too thick, you’re after a honey-like consistency. Add cutlets to the fish sauce and sprinkle with spring onions.
Serve with steamed rice and green vegetables.