Combine eggs, sugar, flour and vanilla. Melt margarine and add to above ingredients, along with the cocoa and pecans. Pour into a greased 9x13 inch pan and bake for 25-30 minutes at 350F.
As soon as cake is baked, top with marshmallows and return to oven until the marshmallows are slightly melted.
Combine margarine and cocoa in saucepan. Melt over medium heat. Add other three ingredients and mix thoroughly. Pour frosting over marshmallows right away. Cool before cutting.
Cajun Country -- New Iberia, Louisiana