1Mix brown sugar,oleo and egg mixture together. Sift flour,soda and salt;add to creamed mixture along with buttermilk. Mix and spread half of batter in a 9x13 inch pan. Spread rhubarb on top. Spread rest of batter on top. Mix sugar and cinnamon; sprinkle on top of batter. Bake at 350 degrees for 20 to 30 minutes. Serve with ice cream or whipped topping. Best Ever!