Tofu is made by curding soymilk made from the mighty soybean, much in the same way cheese is made from milk. Making tofu starts with grinding soybeans with water and heating them.The soymilk is separated from the solids. The hot soymilk is stirred and a natural firming agent known as a coagulant is added.Curds form and when ready they are poured into a forming box and the liquid (whey) is pressed out.aking tofu starts with grinding soybeans with water and heating them. The soymilk is separated from the solids. The hot soymilk is stirred and a natural firming agent known as a coagulant is added. Curds form and when ready they are poured into a forming box and the liquid (whey) is pressed out.