The origin of this recipe goes back to my grandpa's two sisters. They made this cake very often back in the 1970's. I have since taken over making it-and mine is just as their cake was over thirty years ago!
Preheat oven to 350. Grease a 9 x 13 inch dish. Mix water, oatmeal and butter. Let stand 15 minutes. Cream eggs, sugars and vanilla. Add oatmeal mixture. Sift flour and cinnamon. Fold into creamed mixture. Pour into pan. Bake for 30 minutes.
Bring margarine, sugar, milk and vanilla to a boil. Add coconut and nuts. Spread on hot cake and broil for 7 minutes or until bubbly and golden brown. Serve warm.