Rhubarb Cake

3 cups diced rhubarb
2 cups sugar
½ cup shortening or margarine
1 egg, well beaten
1 cup buttermilk
2 cups flour
1 tsp. soda
½ tsp. salt
1 T. cinnamon
1 tsp. vanilla
1 cup nuts

Combine rhubarb with ½ cup sugar, set aside. Cream shortening with remaining sugar. Add egg and beat well. Add dry ingredients alternately with buttermilk, beating well. Add vanilla and rhubarb, then nuts. Bake in 9X13 pan at 350 degrees for 1 hour. Top with whipping cream.