Mix ¼ cup olive, oil, lemon zest, garlic, mint, salt and pepper ingredients together and brush over fillets. Wrap prosciutto all the way around trout in a couple of spots, placing the seam on the skin side. Brush trout all over with remaining ¼ cup of the olive oil. Using a grill on medium-high heat, place skin side down first for about 2-3 minutes and then, using two spatulas (or a fish spatula) turn and cook for another 2-3 minutes. Remove from grill and serve right away.