Add around 1/2 cup of starch, along with salt, to the pork liver. Combine well for a while, so the smelly stuff can be caught. Then wash carefully until your pork liver is clean and no longer slimy.
Add some beer and soak for a while. Then wash again and drain completely.
Add a small pinch of salt and white pepper. Combine well, then add starch to coat evenly.
Heat oil in a small pan until hot, remove the pan from heat. Add scallion, and then combine oyster sauce and light soy sauce, mix well.
Bring a large pot of water to a boil in a wok or pot, then add the pork liver slices. Now turn the fire down to the lowest setting and cover the lid. Set for 2 minutes. Transfer out to serving plate. Spread the sauce from the last step over our simmered pork liver, serve hot.