Preheat oven to 350 degrees and grease a 12-cup Bundt pan with nonstick cooking spray.
Cut the refrigerated biscuits into quarters and place them in a large bowl.
Add the sugar and cinnamon and toss until the biscuit pieces are coated. Place the biscuit pieces in the prepared Bundt pan. Top the pieces with remaining cinnamon sugar mixture.
In a small bowl, combine the melted butter, condensed milk, and brown sugar. Whisk until the ingredients are well combined and a smooth syrup forms.
Pour the syrup over the top of the biscuit pieces.
Bake in preheated oven for 40 to 45 minutes, until the biscuits are golden brown.
Allow the pull apart cake to rest in the pan for 10 minutes, then invert it onto a serving plate to finish cooling.
To make the glaze, beat together the butter and cream cheese until smooth. Add the vanilla extract and powdered sugar and mix until combined. Add the milk one tablespoon at a time, mixing between each addition. Continue adding milk until the desired consistency is reached.
Spread the glaze over the top of the cake before serving.
Be sure to allow your cake to cool for the 10 minutes before inverting onto the plate.