For key visual process photos, refer to the body of the blog post.

Make the cake:

Cup of Yum
1. Preheat oven to 400°F/204°F.
2. Prepare a baking tray or pan (8" by 10" by 1") with parchment paper. Set aside.
3. In a medium bowl, whisk together the egg yolks, avocado oil, milk and salt.
4. Sift in cake flour and mix until just combined. Set aside.
5. In a clean stand mixer bowl, add in the egg whites and cream of tartar and whip until foamy.
6. Gradually add in sugar and whip until egg white meringue reaches soft peaks.
7. Fold the egg whites into the cake flour mixture in 3 additions, until fully combined.
8. Pour the cake batter onto the prepared baking pan and level with an offset spatula.
9. Sprinkle green onion, sesame seeds, pork floss, and seaweed onto the surface of the cake batter.
10. Tap the tray a few times to release any trapped air bubbles.
11. Bake the cake at 400°F/204°F for 15 minutes, or until the top is golden brown and springy to the touch.

Assemble:

1. Remove the cake from the oven, peel off the edges of the parchment paper and transfer to a wire cooling rack to cool for 15 minutes.
2. Carefully flip the cake over onto a new large piece of parchment paper.
3. Peel the parchment paper off the cake.
4. Cut a few shallow lines across (taking care not to cut through) one end of the cake.
5. Spread a thin layer of mayonnaise on the surface.
6. Sprinkle pork floss on the cake.
7. With the parchment paper, carefully roll the cake from the cut side, into a tight Swiss roll, ending with the seam side facing down.
8. Wrap the cake and tuck in the parchment paper.
9. Let the cake sit at room temperature for 30 minutes before slicing.