Rhubarb Platz ( a Mennonite Rhubarb Square )

My Rhubarb Platz

3 cups flour
1/2 teaspoon salt
1 teaspoon baking powder
1 and 1/2 cups white granulated sugar
1/2 cup soft margarine
1 egg yolk
4 tablespoons milk

Rhubarb ( about 4 - 5 cups chopped )

1 cup white sugar
2 tablespoons flour
ground cinnamon

Prepare rhubarb and set aside. In large mixing bowl place the 3 cups flour, the salt, baking powder, and the 1 and 1/2 cups white sugar. Stir thoroughly to blend. Add soft margarine. Rub with hands to form crumbs. In separate small bowl combine egg yolk and milk. Slowly add the egg/milk mixture to the crumbs, be sure to add only enough liquid to make soft crumbles. It may not take all the milk/egg mixture. Place half of crumble mixture into greased 10" by 13" baking pan. Pat down. Place chopped rhubarb onto top. Stir together the 1 cup white sugar and 2 tablespoons flour. Sprinkle sugar mixture over rhubarb. Sprinkle with cinnamon. Cover with remaining crumb mixture. Bake at 350 F oven for 30 - 40 minutes until done, a nice light golden brown.