In a large bowl, add the eggs and a pinch of salt and whisk, then add the pork, mushrooms, bean sprouts, and spring onion and mix well.
In another small bowl or measuring cup, mix together the Gravy ingredients. set aside.
Add some steamed rice to a plate.
Heat the oil in a small non stick pan over medium low heat, when hot, slowly pour in the egg mixture and use the spatula to to keep the mixture into a round patty. Cook for about 3 minutes or until the bottom is golden brown, the egg over and cook until golden brown on the bottom. Flip the egg over again, fold in half, remove from the pan and place on top of the rice on the plate.
In a small pot add the gravy mixture and heat over medium high heat bubbly and well thickened, about 1-2 minutes, stirring continuously. Transfer to a small bowl.
Sprinkle the Egg Foo Young with sliced spring onion and spoon on some gravy, enjoy.