Step 1

Prep: Preheat the oven to 350°F. Line the bottom of a 9x13" pan with parchment paper and set aside.

Step 2

Steep the tea: Pour hot water over 3 of the jasmine tea bags. Cover and steep for 10 minutes. Set aside to cool until needed.

Step 3

Flour mixture: In a small bowl, add the flour and baking powder. Cut open the remaining 2 jasmine tea bags and add the tea leaves. Stir together and set aside.

Step 4

Separate the eggs: Separate the egg whites and egg yolks into two separate large mixing bowls, being careful not to get any of the egg yolks in the egg whites. Set the egg yolks aside.

Step 5

Egg white meringue: To the egg whites, add the cream of tartar. Use an electric hand mixer to beat the egg whites on low-medium speed until it becomes frothy like cappuccino foam.

Step 6

Whip to stiff peaks: Sprinkle in 100g of granulated sugar, one spoonful at a time, mixing well in between each addition. After all the sugar has been added, continue mixing on medium speed until it becomes stiff peaks. Set aside.

Step 7

Egg yolk mixture: To the egg yolks, add the remaining 50g of sugar and mix briefly with the same hand mixer until the eggs are loosened. Add 70g of the cooled jasmine tea, oil, and vanilla extract. Mix to combine.

Step 8

Sift in flour: Use a fine mesh sieve to sift in the flour mixture. Mix again until combined.

Step 9

Combine meringue and egg yolk mixture: Add about 1/3 of the egg white meringue to the egg yolk mixture. Use a spatula to fold them together until mostly combined. Add the rest of the meringue and fold together until no streaks remain.

Step 10

Fill pan: Pour the cake batter into your lined pan. Use an offset spatula to spread the batter into the corners and sides of the pan.

Step 11

Bake: Bake for about 25-27 minutes or until the edges of the cake are lightly browned and the surface of the cake is just beginning to brown. Let the cake cool completely in the pan on a wire rack. Once cooled, run an offset spatula around the edges of the cake and invert the pan to release the cake sheet.

Step 12

Cut out cake rounds: Use a 6" cake ring to cut out 3 cake layers. For the last cake round, cut the cake out in 3-4 pieces from the leftover edges of the cake sheet and arrange them together into a circle. With the scraps, you can either eat them as a snack or save them to make a cake box.

Step 13

Whip: In a medium mixing bowl, add the whipped cream, powdered sugar, and vanilla extract. Use a hand mixer or whisk to beat until it becomes firm peaks.

Step 14

Line cake ring: Place the same 6" cake ring you used to cut out the cake layers down on a cake board or serving plate. Fit a sheet of acetate into the ring. Place the first cake layer into the bottom of the cylinder.

Step 15

Grape layer: Arrange quartered grapes around the edge of the cake, firmly against the acetate. Add finely chopped grapes or halved grapes to the middle of the cake layer.

Step 16

Whipped cream layer: Add a layer of whipped cream on top of the grapes and smooth it out with a spatula. Place the second cake layer on top (I like to use the layer that's made of several pieces as the bottom or the second layer). Repeat with the another layer of grapes, whipped cream, and the last cake layer.

Step 17

Decorate top of the cake: Add another layer of whipped cream on top of the last cake layer. Transfer the remaining whipped cream to a piping bag fitted with a piping tip of your choice. Pipe a few whipped cream dollops on top of the cake. Arrange halved grapes on top of the cake.

Step 18

Chill: Cover and chill the cake in the fridge for at least 4 hours or overnight to allow the whipped cream to set before releasing the cake and slicing.

Step 19

Bonus (optional): With the leftover cake scraps, simply arrange them in a layer in a small container. Add halved green grapes and a layer of whipped cream on top. Enjoy right away or let it chill at the same time as the cake.