Preheat oven to 350°F. Spray a large 10-inch bundt pan with nonstick cooking spray.
Open cans of cinnamon rolls, separate into pieces. Cut each piece into quarters.
Combine granulated sugar and cinnamon in a large ziptop bag or mixing bowl.
Toss cinnamon roll pieces in the cinnamon sugar mixture to coat.
Arrange the pieces in the bundt pan (should be about 2/3 full).
Sprinkle raisins and walnuts on top.
In a small bowl, stir together melted butter and brown sugar. Drizzle over the mixture in the pan.
Bake 30-35 minutes or until dark golden brown and no longer doughy in center.
Remove from oven and cool in pan for 10 minutes. Meanwhile, make the icing.
In a small bowl, mix one pack of icing with 3 drops of green food color.
In another small bowl, mixing the second pack of icing with 3 drops of red color.
Invert the monkey bread onto a serving plate.
Drizzle white, green and red icing over cake. Serve and enjoy!