It is empty to pour oatmeal into a cup. It is not enough to pour 200 ml into a cup, but it must be more than 50 grams.

Let me tell you a way. Divide the remaining cereal into three large portions, divide one large portion into four small portions, see how much a small portion is, and then drink as much as you want. If it's too troublesome, you can grab a small handful by hand every day, and it's almost enough. You try?