Prepare The Filling To make delicious Aloo Parathas, boil the potatoes at least a few hours before you plan to make the parathas, mash them in a large bowl and cover and refrigerate. Take them out from the fridge and add chopped onions, coriander leaves, salt, garam masala powder and red chilli powder. Mix well so that no lumps remain. Ensure that you have finely chopped the onions or the filling will fall out.