Ingredients：
Boiling water：90 g
Earl Grey tea leaves：适量 (to taste)
Cake flour：100 g
Eggs：4
Corn oil：50 g
Whipping cream：适量 (as needed)
Sugar：30 g
Instructions：
1、Pour 90 g of boiling water over an appropriate amount of Earl Grey tea leaves, stir well, strain once, and set aside to cool.
2、In a bowl, combine 4 egg yolks with 50 g of corn oil.
3、Sift 100 g of cake flour into the yolk mixture. (If using cocoa powder, sift it in as well – though not listed, the original text mentions it; you may omit if not using.) Stir until a smooth, lump-free batter forms.
4、In a completely grease?free and water?free bowl, place the 4 egg whites. Add a few drops of vinegar or lemon juice.
5、Beat the egg whites with an electric hand mixer on medium?low speed. Gradually add the 30 g of sugar in three additions, beating until stiff peaks form.
6、Take one?third of the meringue and fold it into the yolk batter using a spatula, lifting from the bottom to combine. Add another one?third and fold again in the same way.
7、Pour the yolk mixture into the remaining meringue and fold gently from the bottom until just combined. Do not stir in circles.
8、Line a baking tray with parchment paper. Pour the batter into the tray, gently tap to release air bubbles.
9、Bake in a preheated oven (temperature not specified; use standard 170–180°C) until done. Remove from the oven and let cool.
10、Whip the whipping cream (Anchor brand recommended) until firm (fully whipped).
11、Spread the whipped cream evenly over the cooled cake surface, then roll up the cake.
12、Remove the ends and cut into slices. Serve.