Espresso Chiffon Cake

Ingredients

• 1/4 cup vegetable oil neutral, such as soybean, canola or vegetable blend
• 6 eggs separated
• 6 tablespoons brewed espresso cooled to room temperature (huntsman recommends freshly-brewed over hydrating espresso powder, which she…
• 2 teaspoons vanilla extract
• 1 1/3 cups cake flour
• 1 1/2 cups sugar
• 1 teaspoon baking powder
• 1/2 teaspoon ground cinnamon
• 1/2 teaspoon salt
• 1/2 teaspoon cream of tartar
• 1/3 cup hot freshly brewed espresso
• 1/3 cup sugar
• 1/3 cup dark rum such as meyer's
• 6 ounces unsweetened chocolate melted and cooled
• 4 1/2 cups confectioners' sugar no need to sift
• 12 ounces unsalted butter at room temperature
• 6 tablespoons half and half or whole milk
• 1 tablespoon vanilla extract