Bin it. Or catch and release. Farm reard rainbow isn't the nicest of fish. Baked in tinfoil with lemon is the standard way for trout. You could fillet it with skin on and pan fry
Rejecting farm reared trout is a death sentence to the species in the wild so please ignore this advice!
Pan fried served with watercress, boiled potatoes and a dressing of 2 tbsp yogurt 1 tsp horseradish, a squeeze of lemon and a pinch of salt.