Moist Black Velvet Cake

Ingredients

• 13 ounces AP flour
• 6 ounces unsalted butter (room temperature)
• 16 ounces granulated sugar
• 4 ounces black cocoa powder
• 2 ounces melted chocolate
• 4 large eggs (room temperature)
• 1 teaspoon salt
• 2 teaspoons baking powder
• 1 teaspoon baking soda
• 4 ounces strong coffee (hot)
• 8 ounces buttermilk (warm (110ºF))
• 4 ounces vegetable oil
• 1 Tablespoon vanilla extract
• 8 ounces unsalted butter (softened)
• 8 ounces vegetable shortening
• 24 ounces sifted powdered sugar
• 2 Tablespoons vanilla extract
• 1/2 teaspoons salt
• 4 Tablespoons milk (or water)
• 2 teaspoons food coloring (optional)