In a medium saucepan, combine margarine, water and chocolate. Bring to a boil, then remove from heat. In a large bowl, mix flour, sugar, baking soda and salt. Pour in margarine mixture and stir to combine. Add beaten eggs and sour cream; mix well. Pour into a greased and floured 10 x 15" jelly roll pan.

Filling: In a smaller mixing bowl, beat together cream cheese, sugar and egg until smooth. Gently drizzle this mixture over chocolate batter. With a spoon or blunt knife, carefully spread around. If using chocolate chips, sprinkle them over the top of the entire cake.

Bake at 375 degrees F for about 30 minutes (best if not over baked.

If ever you need a cake fast, this is it - I once made 2 of these in about an hour and 10 minutes flat - and didn't even break much of a sweat (we won't talk about the speed limit, however, when getting them to the school).