In large bowl, whisk spice cake mix, apple butter, oil and eggs.
With ice cream scoop or large tablespoon, spoon batter into rounded heaps, about 2-3 inches in diameter, onto parchment paper. Space spooned batter 2 inches apart.
Bake 14 minutes. Let cool.
In large bowl, beat cream cheese, butter and powdered sugar until smooth. Add milk and vanilla; beat until blended.
Frost flat sides of pie halves and place halves together.