In a shallow baking dish, mix together the kosher salt, sugar, cilantro, and lemon slices to make the cure. Rub the cure into the trout fillets, and cure in the refrigerator for 2 hours.
Prepare a hot smoker.
Smoke the trout with serrano peppers until the fish is cooked through, but not overcooked. Remove from the smoker and allow to cool.
Peel the smoked peppers and remove seeds. Place the smoked pepper in a blender or food processor and puree. Add the vinegar, olive oil, mango, garlic, black pepper, salt, and tomato. Puree until smooth.
Place the trout on a platter and sprinkle with peanuts. Drizzle a generous amount of the vinaigrette over the trout.