Take all the above ingredients except water in a mixing bowl.
Now add 2 cups of water to the ingredients and whisk or mix well to get rid of any lumps.
Once the batter is smooth and without any lumps, add 3 more cups of water and mix well.
Let the batter rest for 15 minutes. Mix well and if you see that the batter has thickened, you may add another ¼ cup of water. The consistency of the batter must be thin somewhat like buttermilk.
Heat the tawa and once it is nice and hot, spread little oil thoroughly on the tawa.
Now take half cup of the batter and pour on the hot tawa from a height. It should form holes or pores. Do not spread the batter or try to fill the pores.
Drizzle oil on the dosa and cook on medium flame for 2-3 minutes till the edges start browning.
Carefully flip the dosa and cook for another one minute. Dosa is ready, serve hot with chutney of your choice.
For making the next dosa, sprinkle some water on the tawa and again smear some oil on tawa and continue making the dosa.
Notes
Always use fresh bajra flour. Old or aged bajra flour might taste bitter.
You could skip the semolina or rava if you want to make this recipe gluten-free.
Stir the dosa batter well before making each dosa, as the flour might tend to settle down.
Cook the dosa on medium flame to ensure it is cooked well and also becomes crisp. Since this dosa is thin, be careful while flipping to ensure it does not break. If you use a well seasoned cast iron tawa, the dosa will never stick to the tawa.
It is important to sprinkle little water on tawa and smear some oil before making each dosa to get perfect dosas.
You could also make this dosa multi-grain dosa by replacing one portion of bajra flour with jowar flour.