In a wide dish/paraat or you can use your stand mixer as well add the flours, salt, sugar, carrom seeds, yogurt, oil and baking powder. Using fingers rub the flour so that everything is mixed well and the flour is little moistened.
Start incorpotating the spinach puree a little at a time and kneading. Each time you add the puree, let it mix well with the dough.
As the atta absorbs spinach puree,it will start clumping up into a ball.Continue to add till all the dry flour becomes wet, your hands will be mighty messy but the flour will come together.Remember not to add too much puree at a time.
Once a ball is formed, ensure that it is not very dry by trying to squeeze the dough ball between your palms as if making a fist and it should feel firm. Since we added salt to the dough, when the dough will rest it will get a little soft. Start using your knuckles to knead the dough next.
Use your knuckles to flatten the dough out and then pull it all together towards yourself, using your palm & fingers, then knead again with knuckles to flatten out. Knead this way (flatten and bring together) repeatedly for 7-8 minutes.
Towards the last 1-2 minutes of kneading, use both hands to knead for a very smooth & elastic dough (this will work up the gluten really fast). Once the dough looks and feels really really smooth, cover with a kitchen towel and let rest for (not more than) 30 minutes.If you are not planning to make rotis right away, place the dough into an air tight container with lid and refrigerate.
When ready to make rotis, uncover and divide into equal portions.(Note: If you refrigerated the dough, take it out 10-15 minutes before and let sit on kitchen counter).
Take each dough portion between palms of your both hands and roll to make as smooth balls as possible. Flatten the balls. Get some loose atta on another dish.
Set a tawa(griddle) on the stove to heat. Dont use non stick pan or tawa for this recipe. We want the roti to stick to the griddle.
Roll and cover each ball in the loose atta and place on a smooth rolling stone or pastry board or kitchen surface. Flatten out lightly on edges using tips of your finger. Using a rolling-pin, start rolling the dough to a oval shape.Dust the board or the roti as and when required when rolling.
Once rolled, spread 1-1.5 tbsp of water on one side of the roti and immediately place it water side down on the tawa. Keep the flame medium low.
Press a little bit of garlic and sprinkle some nigella seeds on the top of roti. You can press down a little so that they stick to the dough.
In 1-2 minutes,you will see bubbles on top of the roti. At this time, lift the tawa and invert it on direct flame. The roti wil start getting chars, keep on moving the tawa and make sure that entire surface of the roti is nice and charred.
Ideally when the roti is nicely cooked, it will start pulling away from the tawa. Using a large flat spatula, carefully seprate the roti from the griddle and serve rightaway!