Wash, peel and grate the cassava. Place grated cassava in a cloth and squeeze out the excess water. Retain the water. Add water to the "cassava water" to make 1 cup.
Mix the cassava water and flour to form a firm dough. Divide into two and make long rolls. Slice and shape to make dumpling. When the dumpling floats to the top it is ready. Drain and set aside when cooked.