Beat the sugar and egg yolks together until very light in colour. Note: Every now and then you would have to use a spatula to lift the sugar form the sides and bottom as you beat. Of course you have to stop the mixer first.
Sift the flour and set aside.
Mix the almond essence and coconut essence with the lemon juice.
Mix egg whites, cream of tartar and salt together. Beat until very stiff.
Add the flour a little at a time while you beat the egg yolks.
Alternate the flour with the lemon juice until all is used up. Fold in the egg whites.
Pour the batter into a greased pan or tube pan. Bake in a moderate oven for 60 minutes or until a skewer inserted in the center comes out clean. Leave to cool.
For Mango Sauce
Place all ingredients in a blender or food processor and puree until smooth.