Prepare the Bundt Pan: Preheat the oven to 350°F. Generously grease a Bundt pan with butter or baking spray, making sure to coat the center tube and all the grooves.
Cut the Dough: Separate the refrigerated biscuit dough and cut each biscuit into bite-sized pieces. Try to keep the pieces similar in size so they bake evenly.
Coat With Cinnamon Sugar: Combine the granulated sugar and ground cinnamon in a large bowl. Add the dough pieces and gently toss until each piece is evenly coated.
Layer the Dough and Pecans: Arrange the cinnamon-sugar-coated dough pieces in the prepared Bundt pan. Sprinkle chopped pecans between the layers, distributing them evenly throughout the pan.
Make the Gooey Butter Sauce: Melt the butter in a small saucepan over medium-low heat. Stir in the brown sugar, vanilla extract, and salt until smooth and glossy. Do not let the mixture boil aggressively.
Pour the Sauce Over the Dough: Slowly pour the warm butter and brown sugar mixture over the dough pieces. Try to distribute the sauce evenly so it can seep between the layers as the monkey bread bakes.
Bake Until Golden: Bake for 30–35 minutes, or until the monkey bread is puffed, golden brown, and cooked through in the center. If the top starts browning too quickly, loosely cover it with foil.
Cool and Invert: Let the monkey bread rest in the Bundt pan for about 10 minutes. Place a large serving plate over the pan and carefully invert it. Lift the pan slowly and allow the sticky caramel sauce to flow over the bread.
Add the Optional Glaze and Serve: If using the glaze, whisk together the powdered sugar and milk until smooth. Drizzle over the warm monkey bread and sprinkle with additional chopped pecans if desired. Serve warm.