Sabudana vada will break in oil if the dough contains excess moisture or the oil temperature is not right. If excess water is not completely drained off from the soaked sabudana, the dough will contain moisture and break the vada when dropped in oil. To avoid that, once the dough is ready, take a small piece of dough and drop it in hot oil to see if it separates and breaks. If it does, add additional flour, around 1 to 2 tbsp, to the mixture to remove excess moisture, then make vadas or patties and fry. If the oil is too hot, the sabudana will become brown but remain soggy and uncooked. If the oil is cold, it will absorb excess oil and break. The best practice is to fry them on medium to medium-high flame. Once you add the vadas, leave them undisturbed for a few minutes until they firm up and become golden on one side.