Mix the dry ingredientsChop the margarine in small pieces and add to bowlAdd treaclePour the boiling milk over ingredientsAdd the beaten egg and mix all ingredients wellThe boiling milk will melt the margarine and blend the treacle into the dry ingredients to make a sticky sponge mix.Bake the mix in a square baking tin in a medium hot oven (around mark 6 gas/175 electric fan) for 30 minutes or until firm in the middle.