Well in advance of cooking the fish, prepare the Sage Butter by placing all the ingredients in the bowl of a food processor fitted with a metal blade. Pulse to combine well. Using a rubber spatula, heap the mixture onto a sheet of waxed paper and roll to form a sausage shape. Twist the ends to enclose the butter. Set on a plate and refrigerate at least 1 hour to harden enough so that it can be sliced. When the butter is firm enough to slice, remove the paper wrapping and cut it into 1/4-inch rounds, which will be used at the final moment of cooking to season the fish. Keep refrigerated until ready to use. Meanwhile, prepare the stuffing combining the breadcrumbs, pine nuts, jalapenos, garlic, chili powder and salt and pepper in a bowl. Drizzle the 2 tablespoons vegetable oil into this mixture and blend together lightly with a fork.
Preheat the broiler. Brush both sides of the trout with vegetable oil. Season with salt and pepper and broil skin-side up to crisp the skin, a maximum of 2 to 3 minutes. Remove the fish from the broiler. Place the fish, skin-side down, in a roasting pan that has been lightly rubbed with vegetable oil. Sprinkle the stuffing mixture over the fish. Place the fish in a 375-degree oven 6 to 7 minutes to finish cooking. When the fish have nearly finished baking, crumble several pieces of the reserved Sage Butter on each fillet so that, in the last moment of cooking, the butter will melt, seasoning the fish.