70g white sugar (30g for egg yolk, 40g for beaten the egg white)
35g vegetable oil (I often use grape seeds oil)
75g cake flour / plain flour (T45) - sifted
1 tsp vanilla extract (optional)
For the filling
250g heavy cream
30 to 40g white sugar
1~2 tbsp cocoa powder (optional)
1. Making the batter In a bowl, add egg and sugar (30g) and whisk. Add the oil and mix well until combined. Then pour the milk gradually and mix.
2. Finally add the sifted flour and mix until smooth. Set aside. Add vanilla extract if you want.
3. In a large mixing bowl, beat the egg whites until foamy. Gradually add the sugar (40g) and continue beating until stiff and glossy. Set aside.
4. Add one third of this meringue to the batter (egg yolk mixture from #2) and thoroughly mix with an egg whisk. Add the remaining of the meringue and fold into the batter until evenly incorporated, using a rubber spatula.
5. Pour the batter into an un-greased "Angel Food Tube Cake Pan" (17cm diam). Do not coat the pan with butter or any oil. Mix gently the batter with chop sticks to remove any pockets of air inside. Pre-heat the oven to 170℃. Better remove the oven plate as I recommend baking on the wire rack.
6. Bake for about 30min. Or until a cake tester inserted into the center comes out clean.
7. Remove the cake from the oven. Let the cake cool completely in the pan upside down on the rack.
8. Once it is cooled completely, insert a long thin knife around the external sides of the cake (between the cake and the pan) and do the same with eg. a bamboo skewer on the internal sides to detach the cake from the center of the pan.
9. Flip the cake pan over on to a plate and gently remove the side of the pan. Insert the knife along the bottom to remove completely.
10. Whip the heavy cream with sugar (and sifted cocoa powder if you use any) until firm peaks formed and put into a piping bag with a small circle tip or a closed star tip.
11. Using a chop stick or a straw, make about 10 holes from the bottom of the chiffon cake. Pipe the whipped cream into the cake. (into all holes which you made.) Sprinkle with icing sugar over the cake. Chill at least 2 hours before serving.