In a small bowl combine the miso powder with 1 tablespoon of hot water to form a paste. Warm the honey in a microwavable bowl for approximately 1 minute or until hot (be careful, as it can burn quickly). Add the honey to the miso mixture. Put the fish into a resealable plastic bag and add the honey mixture. Seal the bag and refrigerate for up to 4 hours.
Bring a large saucepan of salted water to a boil over medium heat. Add the Chinese long beans and blanch until tender, but not overcooked. Shock the beans in iced water, to stop the cooking and maintain their color. Drain and dry the long beans and either chop into 4 to 6-inch segments or form circles by wrapping the beans around themselves.
In a large skillet add the grapeseed oil and heat until smoking hot. Remove the fish from the marinade and sear in hot skillet until the flesh has an opaque color, about 3 to 4 minutes. Remove the fish from the pan to a large plate and reserve.
For the sauce, using the same skillet, over medium heat, add the onion and saute until translucent, then add the chicken stock, ginger and lemongrass and simmer for 10 minutes. Remove from heat and strain the liquid, discarding the solids.
Return the liquid to a clean skillet, over medium heat. Add the raisins and reduce the liquid by half its volume. Stir in the butter cubes and whisk until the sauce thickens. Remove from heat and allow to rest until needed.
Heat a little grapeseed oil in a medium skillet, over medium heat, and add the long bean circles or strips and saute until golden brown.
To serve, arrange 2 long bean circles in the middle of each plate. Top the beans with a fish fillet and drizzle with the sauce. Garnish with cilantro and lemon.
Cook's Note: to make this dish extra special, you could make a horseradish relish to go on top.