Wash the yam with water. Peel it nicely and then again wash it with water so any dirt if there is removed. Pressure cook it for 4-5 whistles adding salt in it.
After that remove and let it cool and then cut it into slices of any shape you want. Slice it after it is properly cooled so that it cuts with nice edges.
Put some oil on griddle or tava and place them on it and then roast them on both the sides till golden in colour. Roast them on medium heat. Originally instead of roasting ratalu it is deep fried till golden. But this will give the same taste and with less of oil.
Turn both the sides and roast till golden.
Sprinkle all the seasoning and serve hot.
Notes
The same can be prepared with elephant yam, sweet potato, potato and even paneer.If you want to have it during fast then sprinkle the seasoning which can be taken during fast like sindhav salt, black pepper powder.