In a large pan, add oil to reach ½ inch up the sides of the pan. Heat the oil until 350°F or when you drop a pinch of flour into the oil it begins to bubble and lightly brown.
In a wide, shallow bowl, mix together the flour, garlic powder and salt. Dredge smelt in the flour mixture and gently slide into the hot oil. Cook for 2 minutes on each side. Do not overcrowd the pan.
Remove smelt from the oil and drain on a wire rack. Season with salt and pepper while hot. Scatter with herbs and serve hot with lemon wedges and mayonnaise or tartar sauce.
