Preheat oven to 175 degrees C. Grease a 1 litre heat proof bowl or basin.
In large bowl, cream together margarine and sugar. Add, a little at a time each of the beaten eggs, vanilla and flour, until well mixed. Fold in milk to make a smooth consistency.
Pour syrup in bottom of prepared basin and layer batter over the top. Cover basin with firmly tied baking paper covered with foil. Line a deep baking tray with a damp kitchen towel. Place basin on towel inside the tray, and place in the oven. Fill the tray with boiling water to reach halfway up the sides of the basin.
Steam in the oven for 1 to 1 1/2 hours, or until pudding springs back when touched. Check during cooking to se if the water needs topping up. Invert onto serving plate and serve warm.