Dr Pepper sheet cake

Name: Dr Pepper sheet cake
Prep time: 15 min
Cook time: 30 min
Total time: 45 min
Cuisine: American
Ingredients: 2 cups granulated sugar; 2 cups flour; 2 sticks (1 cup) unsalted butter; 1/4 cup cocoa; 1 cup Dr Pepper, preferably made with cane sugar; 2 large eggs, lightly beaten; 1/2 cup buttermilk; 1 teaspoon vanilla extract; 1 teaspoon baking soda; 1 teaspoon ground cinnamon; Pinch kosher salt; ¼ cup Dr Pepper, preferably made with cane sugar; 4 tablespoons unsalted butter; 1 tablespoon vanilla; 1 ½ cups whole roasted pecans; 2 tablespoons granulated sugar; 1 tablespoon ground cinnamon; 1/2 teaspoon kosher salt; Pinch ground clove; 1 stick unsalted butter; 6 tablespoons whole milk; 1 pound (3 1/2 cups) powdered sugar; 1 cup chopped Dr Pepper spiced pecans; 1/2 cup whole Dr Pepper spiced pecans