Preheat oven to 350°F. Generously grease a Bundt pan with cooking spray, making sure to coat every ridge and corner. Spray twice for best results.
In a small bowl, whisk together white sugar and ground cinnamon until evenly combined. Set aside.
Open biscuit cans and separate each biscuit. Cut each biscuit into 4 equal pieces using a sharp knife or kitchen scissors.
Toss each biscuit piece in the cinnamon-sugar mixture until completely coated. Place coated pieces into the greased Bundt pan. Sprinkle any leftover cinnamon sugar over the top.
In a medium bowl, whisk together melted butter and brown sugar until smooth and slightly thick.
Pour the butter-brown sugar mixture evenly over the biscuit pieces in the pan.
Bake for 40-45 minutes, checking at 35 minutes. The monkey bread is done when the top is golden brown, edges are bubbling, and biscuits are cooked through.
Remove from oven and let rest in the pan for 5-10 minutes. Place a large serving platter over the Bundt pan, then carefully flip both together. Gently lift the pan away.
Drizzle prepared caramel sauce generously over the warm monkey bread. Sprinkle flaky sea salt over the top. Serve warm and pull apart with hands.