Ingredients as listed by Arahat is complete but does not tell you how to make Sel Roti. Here are few important steps to follow.
1.Rice flour, sugar & ghee or (butter but not preferred) is to be well mixed till the flour get soaked with ghee. You can feel it by it's color which should be light yellowish by this time.
2. Add little water or milk and mix it slowly. Keep on doing this till you make a dough out of it.
3. Keep the dough in a dish and cover it with lid and let it ferment for 1/2 to 1 hour.
4. Now you can add smashed banana, coconut etc per your taste. Baking soda is not necessary and you can avoid if you want.
5. Take a piece of dough as required in a separate container and add water or milk and make a batter.
5. Pour batter in hot oil at a uniform pace with the help of funnel or spatula and flip it with stick it it gets light brown in color.
** remember, right amount of sugar, ghee & water or milk in batter is essential or you would never be able to get a perfect roundness in Sel Roti. Enjoy & happy tihar