I think the one Pat wants is Rhubarb Custard Cake and is on the third page at this site. I make a similar one that is an upside-down cake and you turn it over after it is baked. This recipe is similar but does not say to turn it upside-down. Here is my recipe and it is our favorite:

Rhubarb Upside Down Cake

Mix together:
1 box White Cake Mix
3 eggs
1 c. water
1 stick oleo

Pour into 9x13" pan.

Mix together:
4 c. diced rhubarb
1-1/2 c. sugar
Spoon on top of cake mixture.

Pour over top of rhubarb:
1/2 pint whipping cream, not whipped.
Bake at 350° for 1 hour. Cool 15 minutes.
Flip upside down on a serving dish.
Garnish with Cool Whip.

Mary Alyce in WI

http://www.nancyskitchen