- 1 (18.25 ounce) package yellow cake mix
- 6 cups chopped rhubarb
- 1 cup white sugar
- 3 cups miniature marshmallows
- Preheat oven to 350 degrees F (175 degrees C). Grease a 9×13 inch pan.
- Place chopped rhubarb on the bottom of greased 9×13 inch pan. Sprinkle sugar evenly over rhubarb. Sprinkle marshmallows over rhubarb and sugar.
- Prepare cake mix according to instructions on package. Pour over rhubarb and marshmallows in pan.
- Bake at 350 degrees F (175 degrees C) for 1 hour. Cool in pan for 10 minutes, then invert onto serving dish so that rhubarb is on top.