Tips for Sucessful Sponge Cake

Below are some important notes to take note for making a successful sponge cake:
1) Preparation Work

• Sift cake flour and baking powder 3 times. This is to lossen up the flour and make the cake soft and light.
• Grease and lay the tin with greased baking paper.
• Preheat oven to 180 degrees celsius.

2) Mixing of Batter with Flour

• It is very important NOT to overmix the batter (especially once flour is added to form batter) as the mixing will cause gluten to form and thus make the finished product hard.

3) Whisk Egg White

• Always whisk egg white last and prior mixing as egg white cannot hold on too long after whisking.
• Use dry, clean and must be GREASE-FREE aluminium bowl to whisk egg white.
• Cream of Tatar help to stablise egg white so as not to deflate so easily.
• Always start with whisking egg white till bubble / foam form before adding cream of tartar.
• Then gradually add in the egg white
• Medium Stiff is the best consituency for sponge cake (too soft - cake flaten easily and too stiff - difficult to blend egg yolk mixture with egg white and end up a lot of folding)

4) Folding of Egg Mixture

• Always start with mixing 1/3 of egg white to the thicker mixture (egg yolk) to balance out the consituency and before blending the mixed batter to balance egg white.
• If need be, sometime blend egg white and yolk few times before final folding.
• Folding meaning using spatula to go one round of batter in clockwise direction following by cutting the batter at 12 0'clock position and lift up the spatula to fold in the batter. 
• Alternatively, use manual ballon whisk to fold batter in a circular motion like merry-go-round.
• Use swift and light stroke and fold the batter quickly.
• Always end the folding position by lifting up the spatula to fold in the batter.

5) Post Mixing

• Bang the baking tin prior placing it in the oven for about 5 times to get rid of any remaining air bubbles.
• Wrapping baking tin with wet Wilton's baking strips or wet towel. This help to prevent the cake top to be cracked and dome shaped.

6) Baking

• Bake immediately when mixing is complete else batter will deflate and cake will sink.
• Temperature Control (too hot - cake dry and will crack else sometime outside cook but inside still not cook)
• Bake in oven's at bottom rack.
• Cover the top with aluminium foil when the top is nicely brown and smell start to come off from the oven. (This is to avoid top from burning).

7) Post Baking

• Check if cake is done using 4 fingers to gently tab the cake surface. If finger dents are formed, cake is not cooked yet. If cake bounce back with the tapping without any funger dents, cake is cooked.
• Drop cake tin at height of 25cm onto table top to shock the cake and reduce shrinkage.
• Overturn the cake tin once remove from the oven to prevent the cake from collapsing and shrink in height.