Beat eggs until light and lemon colored.
Slowly add the sugar, beating constantly.
Add water and vanilla and beat well.
Sift together flour and baking powder and fold into batter a little at a time.
Pour into a well buttered and floured 9 inch (23 cm) cake pan.
Bake in a 350Â°F (180Â°C) oven for about 30 minutes.
Cool in pan.
Remove and spread topping over the cake.