Chocolate Cake Doughnuts

INGREDIENTS

• 1 1/2 cups white sugar
• 1 teaspoon baking soda
• 2 eggs
• 1/2 teaspoon salt
• 4 tablespoons butter
• 3 (1 ounce) squares unsweetened chocolate
• 1 1/2 teaspoons vanilla extract
• 1 cup buttermilk
• 3 1/2 cups all-purpose flour
• 3 teaspoons baking powder
• 1 cup confectioners' sugar
• 1 egg white
• 1/2 teaspoon vanilla extract
• 1 quart vegetable oil for frying