Beat egg whites until foamy and fluffy, add in sugar a little at time while keep beating, and keep beating until thickened/firming
Add ovalet while keep beating, and beat for 2 minutes long
Turn off mixer, add in a little coconut milk, stir with spatula then add in a little flour, stir. Repeat this step until coconut milk and flour all used up and mixed well.
Divide batter into 3 equal portions. One leave it as is while the other two, mixed with cocopandan essence and pandan paste.
Preheat oven to 350 F, grease a rectangular pan (20x29x4), lay a parchment paper on it and grease the paper as well.
Pour 1 cup of regular batter, spread evenly and bake for 5 minutes. Pour the next color for a cup as well, and bake for 5 minutes, follow with the last color. Repeat step, each time one cup and 5 minutes, so you are making layers.
Once all batter used up, bake the whole cake for 20-25 minutes.
Cool to room temperature and slice.