Root Beer Cake

Ingredients

• butter, for the pan
• 1 1/2 cups plus 1 tablespoon all-purpose flour
• one 12-ounce bottle (1 1/4 cups) root beer
• 1/2 cup molasses
• 1/2 teaspoon plus 1/8 teaspoon baking soda
• 3/4 cup dark brown sugar
• 1/4 cup plus 2 tablespoons vegetable oil
• 3 tablespoons plus 1 teaspoon granulated sugar
• one 1-inch piece fresh ginger, peeled and grated on a microplane or on the finest side of a box grater (this should yield about 1 teaspoon)
• 2 teaspoons vanilla extract
• 1 large egg
• 1 3/4 teaspoons baking powder
• 1 1/4 teaspoons ground star anise
• 1 1/2 teaspoons ground cardamom
• 1/2 whole nutmeg, freshly grated, or 2 teaspoons finely ground nutmeg
• finely grated zest of 2 lemons, preferably organic
• 1 teaspoon kosher salt
• 1/2 teaspoon freshly ground black pepper
• 3/4 cup heavy cream
• 1 tablespoon sassafras bark or 1/2 teaspoon sassafras extract
• 2 cups confectioners’ sugar
• pinch ground star anise
• pinch ground cardamom
• 1/4 teaspoon kosher salt
• 1/4 whole nutmeg, grated, or about 1 teaspoon ground nutmeg
• freshly grated zest of 1/2 lemon, preferably organic