Preheat oven to 350 degrees.
With a stand or a hand mixer, cream together 10 tbsp softened butter and granulated sugar.
Begin mixing in one egg at a time.
Add flour a bit at a time, mixing between additions (I typically add in about 1/2 c at a time).
Add baking powder, salt, and cinnamon and continue to thoroughly mix. Scrape the sides of the bowl periodically to ensure everything gets blended properly.
Mix in milk, apple butter, and vanilla until the batter is evenly mixed together. Pour batter into a deep greased 9x13" cake pan and bake at 350 for 30-35 minutes. Check cake at 30 minutes with a toothpick - if it comes out clean, remove from oven. If not, give it another 5 minutes of bake time.
(A few minutes before cake comes out of the oven, you can start making the caramel sauce - recipe below).
Remove cake from oven and evenly poke holes across the top (reaching all the way to the bottom of the pan) using the end of a wooden spoon.
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