Heat oven to 350. Spray a 10" bundt pan w/ cooking spray. Separate biscuits. Cut each biscuit into 6 pieces, place in a lg bowl.
Pour butter over biscuit pieces. In another bowl, mix together sugar, raisins, nuts and cinnamon. Sprinkle mix over biscuits. Toss everything to coat evenly.
Place biscuit mix into pan, evenly. Bake 30-35 min or until set in the middle. Let cool and then invert onto a plate. In small bowl, whisk together powdered sugar and milk. Drizzle over cake and serve.