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.

In a medium saucepan, combine the cream, sugar and lemon juice. Bring to a gentle boil over medium heat, stirring occasionally to dissolve the sugar. Remove from the heat.

Beat the egg yolks in a medium bowl. Whisk 1/2 cup of the hot cream into the egg yolks. Whisking, gradually add the egg mixture in a slow, steady stream, to the hot cream. Cook over medium-low heat, stirring occasionally, until the mixture thickens enough to coat the back of a spoon, about 5 minutes. Remove from the heat and stir in the sour cream in 4 additions. Strain through a fine mesh strainer into a clean container. Cover with plastic wrap, pressing down against the surface to keep a skin from forming. Refrigerate until well chilled, at least 2 hours.

Remove from the refrigerator and pour into the bowl of an ice cream machine. Freeze according to the manufacturer's instructions. Transfer to an airtight container and freeze until ready to serve.