How to Make It
Prepare the Cupcakes: Preheat oven to 350°F. Place cupcake liners in 24 muffin cups. Whisk together cake mix, pumpkin, eggs, oil, and coffee in a large bowl until fully combined. Divide batter evenly among muffin cups (about 1/4 cup per cup).
Bake in preheated oven until a wooden toothpick inserted comes out with moist crumbs, about 20 minutes. Cool on a wire rack until completely cooled, about 30 minutes.
Prepare the Frosting: Beat butter with an electric mixer on medium speed until fluffy and lightened in color, about 3 minutes. With mixer running on low speed, slowly add powdered sugar, 1/2 cup at a time, until fully combined. Slowly drizzle in whipping cream, and beat until frosting is smooth and fluffy. Add salt, and beat 1 minute. Fill a piping bag with buttercream, and pipe onto cupcakes. Drizzle with caramel sauce and sprinkle with pumpkin pie spice, if desired.