01 - Preheat oven to 350°F (180°C) and thoroughly grease a bundt pan with unsalted butter or nonstick spray.
02 - Open the biscuit or cinnamon roll dough. If using biscuits, quarter each piece; if using cinnamon rolls, unroll and cut into bite-sized pieces.
03 - In a medium mixing bowl, combine granulated sugar and ground cinnamon. Toss each dough piece in the cinnamon sugar mixture until evenly coated.
04 - Arrange the coated dough segments evenly in the prepared bundt pan, layering them for optimal texture.
05 - In a small bowl, whisk together melted butter, light brown sugar, and vanilla extract. Drizzle evenly over the dough layers in the pan.
06 - Bake for 30 to 35 minutes, or until the top is deeply golden and the dough is cooked through.
07 - Allow to cool in the pan for 10 minutes, then carefully invert monkey bread onto a serving plate.
08 - While bread cools slightly, whisk powdered sugar, milk, and vanilla extract until smooth. Drizzle icing generously over warm bread.