Prepare all of the ingredients and peel and cut the potato into small pieces.
In a pot, add water, salt, and the potato and boil it until it is cooked.
Drain and mash the potatoes, then add the butter.
Add salt, garlic powder, and white pepper and mix well.
Add the milk gradually. To make the gravy, dissolve the beef cube.
In 2 cups of water in a pan, then add the butter and flour mixture gradually into the pan.
When the sauce is thick, add the chicken evaporated, soy sauce, and black pepper, and it's ready to serve.