Put the sugar, butter, flour, eggs and milk into a bowl and mix together using an electric mixer. Use a spatula, go round the edges to ensure all ingredients are incorporated.
Spoon into the prepared tray and flatten down. Place in the microwave for 5 minutes. After this check it, it may need longer. The top should be spongy. When you cook a sponge in the microwave it does not brown on the top, but stays a yellowy sponge colour but it is definitely cooked.
Leave to cool in the tray for about 10 minutes.
Put 110g (4oz) of the icing sugar into a bowl and mix with the warm water so it is thick enough to coat the back of a spoon. Spread all over the cake and leave to set.
Meanwhile mix the rest of the icing sugar with warm water, a teaspoon at a time again, and add some red food colouring to make a vivid red colouring. Spread this on top of the cake either using the back of the spoon, or a piping bag in the shape of the St George's cross.
Leave to set, cut and enjoy, whilst supporting your team!
Decorate in the colours of your team, it doesn't have to be England. Experiment with other food colourings. If you don't like football you could always try other designs on the top.
Easy to make. Tastes OK. Would have been helpful if size of microwave dish had been specified/suggested - I ended up using 12 x 16 cm - and there is not enough to serve 12 people, even after I've added butter-cream icing inside. - 19 Aug 2011