½tspcream of tartaror use lemon juice or white vinegar
Instructions
Make sure your chiffon cake pan does not have a non-stick coating or your cake will not rise. The cake needs to cling to the side of the pan to rise tall
I strongly suggest weighing the ingredients including the egg yolks and the whites because the size of the eggs may vary. If the eggs are off by a few grams, it's not really a big deal
Get the eggs out of the fridge and separate them when they are still cold. They are easier to separate when they are cold. Let the yolks and the whites come to a room temperature, this may take about 30 minutes or so
Preheat the oven to 330 F (165 C) for conventional oven, 310 F (150 C) for convection oven
Prepare the cake batter:
Whisk the cake flour with the oil first. This helps to prevent the gluten from forming.
Then add egg yolks, milk, vanilla extract, and salt. Whisk to combine. The batter is thick but flowy
Prepare the meringue:
Beat the egg whites on medium speed until frothy
Add cream of tartar or lemon juice/vinegar and whip until it turns whitish and air bubbles are fine.
Gradually add sugar as you beat, in 3 batches. I beat them at medium speed (speed 6 on Kitchen Aid). This will take a bit longer compared to beating at high speed. I used to do higher speed (speed 8), but the meringue is smoother and nicer when I maintain the speed on 6 and much more stable too. I highly recommend stopping several times to check on the consistency and scraping the sides of the bowl to make sure no sugar left on the side of the bowl.
Whip until you reach a stiff peak but still have a slight bent on the tip. Then lower the speed to 4 and whip for 1 minute to even out large bubbles and stop beating
Fold the meringue into the cake batter:
Gently fold 1/3 of the meringue into the thick batter. Using a whisk, using a cutting motion and fold over to mix. Repeat this motion several rounds. Continue on with the second 1/3 of the meringue again to mix.
For the last 1/3 of the meringue, use a rubber spatula instead to ensure you get all the batter at the bottom of the bowl mixed in as well. Use a cut down in the middle
Then fold-over motion to fold gently but quickly. Make sure you don't see any more white meringue.
The mixture should be fluffy and voluminous.
Pour the batter into an UNGREASED chiffon cake pan.
Use a chopstick or a skewer to draw a zig zag on the cake batter to pop any large air bubbles that are trapped inside and also to even out the batter. The large air bubbles will create large holes in the crumbs later. Gently drop the cake pan from about 10 cm height on the counter 2-3 times.
Bake the cake:
Put the chiffon pan in the middle rack and let it bake for 40-45 minutes for 6-inch cake, 45-50 minutes for 7-inch cake . The time is just for reference. Your oven may need less or more time to bake.
Test for doneness:
I know this is weird to say, but it's actually "safer" to overbake chiffon cake than underbaking. Underbaking tends to cause the cake to collapse. The surface should be dry to touch and bounce back slightly when you gently pressing on it. If you insert a skewer towards the center of the cake, it should come out clean. If not, bake for another 5 minutes
Don't be alarmed if your cake has some cracks on top. What you are looking at will become the bottom of your cake. I know many people mind it a lot and make a big fuss when the top of the chiffon cake cracks, but it's not a flaw.
Cooling:
Drop the cake pan from about 10 cm height on the counter several times to prevent shrinkage when you pull the cake out of the oven. Then carefully invert the pan upside down immediately. Please don't be tempted to remove it from the pan if it's still warm. It takes about one to two hours to cool down completely
Once it has cooled down completely, use a spatula knife to run through the edge and the outer center of the tube to help release the cake. Gently push the base to lift the cake out. Use the knife again to run through the base of the pan and then carefully release the cake
You can gently scrape off the brown crust from the side of the cake for a cleaner look
Storing:
The cake can be kept in an air-tight container for 2-3 days