Preheat the oven to 350°F and spray a 9×13 pan with cooking spray.
Mix the cake mix, milk, eggs, and oil for 2 minutes, then pour the batter into the prepared pan.
Bake for 21-26 minutes, then poke holes all over the cake with the back of a wooden spoon.
Make cranberry sauce by boiling cranberries, sugar, and water until they pop, then stir in vanilla and butter; cool.
Prepare the frosting by whipping cream cheese, powdered sugar, vanilla, and heavy cream until soft peaks form.
Assemble by spreading cranberry sauce over the cake, topping with frosting, and garnishing with sparkling sugar and pecans.