Grease baking pans
Place sugar and eggs in heat proof mixing bowl.
Steam (uncovered) –place bowl over hot water in large saucepan (bowl not touching water)
Heat over low heat, stirring occasionally for 5-10 mins till mixture is lukewarm.
Remove bowl from saucepan, stir in vanilla.
Beat egg mixture with electric mixer on hi-speed for 10 mins.
Sift in 1/3 of flour over egg mixture and fold in. Repeat to sift and fold (1/3 flour at a time)
Lastly, gently fold in melted butter. Spread in pans.
Bake in 350F oven for 25-30 mins til done. Cool in pans, transfer to rack,let Cool.