In a large pot, heat some water and add the spinach leaves along with some salt. Allow them to blanch for 5-6 minutes. Drain the hot water from the spinach leaves and run them under cold tap water.
Grind the spinach leaves along with ginger and make a fine puree. This puree approximately came up to ¾ Cup. Add very little water if required. **In case you are not making it for kids, you can include green chillies to grind along with the spinach leaves.
In a large mixing bowl, combine the spinach puree, wheat flour, salt, cumin powder and mango powder and start kneading. Add a little more water as you knead until you achieve soft pliable dough. Splash the oil onto your hands and the remaining on the dough and knead until we have a clean bowl. Set the dough aside for 20 Minutes or so.
Divide the dough into 20 equal portions. Pick one portion of dough at a time, dust some flour and spread them with the roller into thin phulkas. Heat a non-stick pan / tava and cook each phulka on the pan slightly for a few minutes until you start to see some bubbles. Flip the phulka and cook for another a minute or so . Now put the phulka on the flame carefully , watch them begin to puff up slowly. Flip it and allow it puff up on the other side as well. Remove from the flame and apply some ghee, if you like. Pile them into a casserole and serve them along with a paneer curry or just some yogurt and pickle.
Incase you do not want to flame bake it, you may cook for a few more minutes on the pan. Put a gentle pressure using a flat spatula on each side and then set them aside in a casserole to keep it warm.
When you are serving the kids, you may let them roll and enjoy it as it is or dunk it in some yogurt.