Preheat the oven to 160 C / Gas 2 1/2. Line a deep round (23cm) baking tin with greaseproof paper.
Cream the margarine or butter and the caster sugar together in a bowl until light and fluffy.
In a separate bowl beat the eggs and the milk with a fork. Add alternate spoonfuls of all the egg mixture and the all flour into the butter mixture until all is consumed and whisk until smooth,
then beat in the vanilla extract. Spoon the cake mixture into the cake tin.
Bake in the oven for 1 -1/4 hours or until risen and golden brown. Leave for 10 minutes in the tin then remove gently and put onto a wire cooling rack and leave to cool completely.
When the cake has had its full time in the oven or is risen and golden brown, insert a skewer into the centre of the cake. If it comes out clean, then it is cooked; if it is wet then return the cake to the oven to bake for a few more minutes.
This is a fantastic recipe, i use it all the time and it has never ever let me down, stays moist for days, great for birthday cakes etc - i have also used Gluten Free Flour in this recipe and it works everytime - 24 Nov 2013