Step 1: Preheat your oven to 170°C (340°F) and line a 10×12 inch Swiss roll pan with parchment paper.
Step 2: In a medium bowl, whisk the egg yolks with 20g of sugar until pale and frothy.
Step 3: Add the coconut milk, vegetable oil, and pandan extract to the yolk mixture, whisking until well combined for the pandan swiss roll base.
Step 4: Sift the cake flour, cornstarch, and salt into the yolk mixture and whisk until smooth.
Step 5: In a separate clean bowl, beat the egg whites with cream of tartar until foamy, then gradually add 60g of sugar, beating until stiff, glossy peaks form.
Step 6: Gently fold one-third of the meringue into the pandan batter, then fold the rest in using a light touch to maintain the air.
Step 7: Pour the batter into the prepared pan, smooth the top, and tap the pan on the counter to remove large bubbles.
Step 8: Bake for 12-15 minutes or until the sponge springs back when touched.
Step 9: Immediately flip the cake onto a clean kitchen towel dusted with powdered sugar, peel off the parchment, and roll the cake tightly while warm.
Step 10: Once cooled, unroll gently, spread with whipped cream (beaten with powdered sugar), and roll back up before chilling for 1 hour.