Steam or boil the sweet potatoes (with the skin on) until they are very soft. Check with a fork to see if they are cooked and then, take them out of the pan.
Allow them to cool for a couple of minutes but try to peel them while they are still quite hot. We need them to be hot or at least warm in this recipe.
Use a fork if it helps to peel them while they are hot. Then mash the sweet potatoes. If you are using leftover sweet potatoes, reheat them until they are hot before using them in this recipe.
In a mixing bowl, add one cup of all purpose flour. Add in the mashed sweet potato. Start by mixing with a fork as the sweet potato will be too hot to handle at this stage.
Once the mixture is okay to handle, continue the mixing with your hand and work the mixture until a dough is formed. Once the dough is formed, do not overwork it as it may start to get sticky and then you will need to add more flour which will result in a hard roti.
Flour the work surface and place the dough on it. Roll it into a thick log. Then cut the log into 6 equal portions.
Keep a bowl of flour close by. Dust your hands with a little flour and take one piece of dough. Roll it in between your palms into a ball then lightly flatten it. Dip the ball into the bowl of flour and cover it with flour on both sides. Now lightly flatten the edge of the ball with your thumb and first finger. This will help keep its round shape when we roll it out.
Set the floured ball aside or place it back into the mixing bowl. Do the same for the rest of the pieces.
Take one ball and place on the work surface or board. Begin to roll it out. Turn it on the other side and continue to roll out by applying even pressure so that the roti can rotate on itself to create a nice round shape. Flour the roti if you need to but not too much as this may result in a hard flatbread. Roll out until the roti is about 2 mm thick.
Meanwhile, heat a tawa, skillet or crepe pan on medium heat. When the pan is hot, place the roti on it and allow it to cook for 20 to 30 seconds. Then flip the roti at 30 second intervals. When the roti starts to bubble, leave it to cook for a little longer than 30 seconds before flipping. The bubbles mean that the hot air is cooking it from the inside too. Cook the roti for a total of two to two and a half minutes.
Store the roti in a container or plate lined with a clean tea towel. Always keep the rotis covered with the tea towel to keep them soft. This will also prevent them for getting soggy with the steam in the container.
Now repeat for the rest of the rotis. Adjust the temperature of the skillet as needed when it gets too hot. Brush off any loose flour on the pan before adding the next roti.
Occasionally, flip the rotis in the container so that the last one is sandwiched in between the other flatbreads. This helps to further soften them.