Maybe this is what you are looking for:

Rhubarb pudding cake

Directions
Preheat oven to 350° F.
Prepare baking pan with cooking spray. In large mixing bowl sift together sugar, flour, baking powder and salt. Add butter, milk and vanilla; beat on medium until all ingredients are combined. Add egg; continue beating. Batter will be thick.
Place cut rhubarb on bottom of prepared baking pan, cover with batter, spreading evenly over rhubarb.
In a small bowl combine sugar, corn starch and cinnamon, stirring until combined. Sprinkle over top of batter evenly. Carefully pour boiling water over topping.
Bake 60 minutes, or until a toothpick comes out clean when inserted half way down. Bottom layer will be moist.
Serve warm or cool - garnish as desired with whipped topping or ice cream.
Container: 9" x 9" x 2" square baking pan, large mixing bowl
Prep Time: 20 minutes
Cook Time: 1 hour
Serving Description: 1 square
Servings: 9


Ingredients
- 4 1/2 cups rhubarb, chopped
- 2 cups all purpose flour
- 1 1/2 cups sugar
- 2 teaspoons baking powder
- 1/2 teaspoon salt
- 5 tablespoons butter, melted
- 2/3 cup milk
- 1 teaspoon vanilla
- 1 egg
TOPPING:
- 3/4 cup sugar
- 1 tablespoon cornstarch
- 1 teaspoon cinnamon
- 1 1/4 cups boiling water

Thank you Glenda. Thats what I'm looking for.

You are so welcome!

Looks like a good recipe. I love rhubarb, I'm going to try this one.