Cream sugar and oleo; add egg, salt and vanilla. Add sour milk alternately with flour and baking powder and soda which has been sifted together. Fold in rhubarb. Pour into a well greased (with oleo) pan sprinkled with brown sugar. Top with 1/2 cup of brown sugar and sprinkle with chopped nuts. Bake at 350 for 30 to 35 minutes. Top with whipped cream.