Swiss rolls of all flavors are a staple at Chinese bakeries. I love this version because it celebrates the use of high-quality tea in baking.
Technique tip: When infusing the cream with jasmine tea, you want to simmer the cream very gently. You don't want to reduce the cream because it won't make for a very fluffy and airy whipped cream. After assembling the Swiss roll, make sure to properly chill it and then cut with a sharp serrated knife for clean cuts.
Swap option: Instead of jasmine tea, you can experiment with early gray or any other high-quality loose-leaf tea for the infused whipped cream.
For jasmine whipped cream:1.
In a small saucepan, combine the cream and tea leaves. Bring to a simmer over low heat and gently simmer for 5 minutes. Turn off the heat, cover with a lid and allow the tea to steep for 15 minutes.2.
Strain the cream into a bowl and discard the tea leaves. Cover the cream and refrigerate until chilled, at least 2 hours or up to 3 days.3.
In the bowl of an electric mixer fitted with the whisk attachment, beat the chilled cream, sugar and salt on medium speed to form medium-stiff peaks, 3 to 4 minutes. Store the whipped cream in the fridge until ready to assemble the Swiss roll.
For the matcha sponge cake:1.
Preheat the oven to 350 F and line a large, rimmed baking sheet (half sheet pan) with parchment paper.2.
In a medium bowl, whisk to combine the cake flour, matcha powder, cornstarch, baking powder and salt.3.
Place the egg whites in the bowl of an electric mixer fitted with the whisk attachment. Place the egg yolks in a separate large mixing bowl. Whisk the egg whites on medium speed until foamy, 1 to 2 minutes. Add 1/4 cup of the sugar and the cream of tartar, increase the speed to medium-high, and whisk until stiff peaks form, 5 to 7 minutes.4.
To the yolks, add the remaining 1/4 cup sugar, the canola oil and vanilla. Vigorously whisk until pale and smooth, about 3 minutes. Using a flexible spatula, scoop 1 cup egg white mixture and fold into the egg yolk mixture until fully incorporated. Fold the remaining egg white mixture into the yolk mixture in three additions, alternating each addition with half the flour mixture and reaching to the bottom and around the sides of the bowl as you fold so that no traces of flour remain. Take care not to deflate the beaten egg whites too much as you fold.5.
Transfer the batter to the prepared baking sheet and smooth the top using an offset spatula. Make sure the batter is even and reaches the edges of the sheet. Bake until the center is set and the top is lightly golden-brown, 10 to 12 minutes.6.
Transfer the baking sheet to a wire cooling rack and allow the cake to cool for 10 minutes. Run an offset spatula around the edges of the pan to help release the cake. Starting from one short side, carefully roll up the cake into a log, using the parchment paper to assist you. Once rolled, allow the cake to cool for 10 more minutes. Unroll the cake and allow it to cool completely. A very thin layer of cake may stick to the parchment paper, but that's natural.
Spread the whipped cream on the cake in an even layer, and starting from a short side, carefully and tightly roll up the cake. Set the cake seam-side down and wrap in parchment paper or plastic wrap. Chill in the fridge for at least 1 hour, or up to overnight, to set. Slice with a sharp knife and serve.