Blend the beetroot, ginger and green chilies to a smooth paste.
In a bowl mix together flour, salt, baking powder, baking soda, yoghurt, puree and mustard oil.
Add water as required to knead it into a soft dough. Cover it and keep it in a warm place for 4-5 hours. Add a tsp. of oil and knead again for a minute. Divide into 4-5 equal portions. Roll out each ball of dough into an oblong shape by dusting some flour. Sprinkle some garlic, chilies and coriander leaves over it. Roll once again so they stick to the dough.
Heat a tawa / griddle till it is smoking hot. Apply some water to the other side of the rolled out dough and place it on the hot tawa.
After 1-2 minutes, you will see little bubbles appearing on the surface.
Flip the tawa over the direct flame and to cook the other side too.
Transfer to a serving plate and brush with butter / olive oil.
Enjoy them hot with any side dish of your choice.
