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I would like to know what are the causes for a chiffon cake to have a caved in centre.
After baking, the cake turns out with a nice dome. The cake is overturned immediately to cool. But after about 15 minutes of cooling, the centre of the cake which was previously a dome became caved in (not too deeply caved in, maybe just about 2cm from the level of the cake height.)
So the result after the cake is cooled, the top of the cake (which was previously the bottom) is light and fluffy and the bottom of the cake (which was previously the top) is dense.
The sides and bottom of the cake are evenly browned. The sides do not shrink as much as the centre.
The cake is baked at 160C-Fan for 45min for a 5-egg recipe. I use cake flour and a very small amount of baking powder.