In a pot, heat vegetable oil for 1 minute on low heat.
[Ingredient A] Place flour in a bowl and pour in heated vegetable oil. Stir and mix until smooth. Add milk and egg yolk and mix well.
[Ingredient B] In a whisking bowl of a standing mixer, place egg white and salt and beat until foamy. Add the sugar gradually while the mixer continues beating the egg. Beat until you achieve stiff peak.
Use a spatula to add Ingredient B to Ingredient A gradually. Fold the batter swiftly and lightly until batter well combined.
Grease inner pot with butter. Pour half of the batter and sprinkle meat floss and spring onion on top. Then pour the other half and select “Cake” function. Adjust timing to 45 minutes.
Once done, overturn the pot to take out the cake. Let it cool and squeeze mayonnaise on the cake. Lastly, sprinkle meat floss and spring onion.