• Get the eggs, milk (if using milk) or soda drink (if refrigerated) out on the counter 15-20 minutes before you plan to bake. We want them at room temperature
• Mix cake flour, salt, baking soda and baking powder (if using the latter two as leaveners instead of soda drink). Set aside
• Place the eggs, sugar, and matcha powder in a mixing bowl. Use a whisk attachment and beat on medium speed for 1 minute and then increase to high speed (6 on a kitchen aid), add 1 teaspoon of vinegar (only if you choose to use baking soda and baking powder instead of soda drink) and continue to beat for 10-12 minutes. It is crucial to beat it this long so the cake will be light like a sponge
• The batter will triple in volume, and turn pale (well, greenish pale in this case). Reduce the speed to low. Gradually add in flour mixture, alternating with the soda drink (if using soda drink) or milk. We don't want to overwork the flour, just want to mix it in and no more lumps. Stop the mixer and use a rubber spatula to give it a few stirs in there 
• Prepare a 5-6 inch stainless steel or aluminum round pan. I use 5 x 3 inch round aluminum pan. Line the pan with parchment paper.  Pour the batter into the prepared pan and drop it on the countertop 4-5 times to break any bubbles. You don't need to cover the cake with an aluminum foil

Preparing the Instant Pot:

• Place the trivet in the pot. Pour 2 cups of water in the pot (using standard U.S. measuring cup). Press saute and bring the water to a boil while the eggs are beating. Be careful and gently place the container inside the pot on top of the trivet. Turn off saute mode. Close the lid. Remember to place the steam release to SEALED. Press "Pressure Cooker" and click on pressure level and choose HIGH PRESSURE. Use +/- to set the time to 30 minutes. Add 10 minutes if you use a glass dish to cook the cake. It will pressurize quickly now since we have boiled the water before
• When it's done cooking, do a natural release and the valve will collapse on its own. Then carefully turn the steam release valve to VENTING and let the steam all come out and no more hissing. Open the lid and very carefully lift the trivet by its handle to remove the container out. Lift the 2 sides of the parchment paper to lift the cake out from the container. Let cool for 10 minutes. The cake will be very soft and spongy

If you steam the cake in a regular steamer:

• You need a steamer with a tall lid like this. Make sure you have enough water in the steamer and it has comes to a rolling boil. Carefully placed the cake in there and secure the lid and let it steams on high heat for 30-45 minutes or until toothpick inserted comes out clean. If you double up the recipe and use 8-10 inch container, you need to increase the steaming time to 50 minutes or until the toothpick inserted in the middle of the cake comes out clean. It is important not to open the lid during cooking time (at least the first 30 minutes), so you need to make sure your steamer can hold enough water for at least 30 minutes. If you need to refill water, make sure to refill with hot water and continue with steaming