In a mixing bowl, beat the sugar and egg until thickened and pale yellow in color. Beat in the butter, vanilla and salt. Gently stir in the flour, being careful not to overmix. Allow the batter to rest at room temperature at least 15 minutes.
Lightly grease your pizzelle iron. Preheat the iron on the stove over medium heat (if you're using an electric model, follow the manufacturer's directions.)
If using a 5-inch pizzelle iron, use 1 1/2 tablespoons batter; if using an 8-inch iron, use 2 tablespoons. Close the pizzelle and cook for 45 seconds on 1 side. Turn the iron over and continue to cook until lightly golden, about 45 seconds more. Adjust heat as necessary. Open the iron and remove the waffle with a fork or thin spatula.
While still hot, quickly roll the waffle around a cone-shaped mold, sealing the point. (The cones will harden as they cool; remove from the mold when cool.)
To serve, fill the each pizzelle cone with scoops of Sour Cream Ice Cream and garnish with chocolate shavings.
Yield: 6 to 8 servings