In a large bowl, mix together flour, baking soda, sugar and salt. Stir to combine well.
Add yogurt and oil and knead into the flour. Start adding water little by little and knead as you go till you get a soft, supple dough. You may not need the entire quantity of water so add only as much as you require. If the dough feels too dry, add water by the teaspoon or some extra flour if the dough feels little wet. (watch the video above to see how the dough should feel)
Cover with a damp towel and set aside in a warm place for 25-30 minutes. If you live in a cold place, rest the dough for 1.5-2 hours. But in warmer climate, 30 minutes is sufficient.
Heat a flat non-stick pan or skillet or tawa. I love using a cast iron tava.
Divide the dough into lemon sized balls. Dust a ball of dough in flour. Lightly roll out the dough to 1/4 inch thickness without applying too much force. Use a little dry flour if the dough is sticky. The shape doesn't matter.
Brush the top lightly with water, and sprinkle with sesame and onion seeds (kalonji) and chopped garlic. Lightly press so that they stick to the dough. Turn it over, and brush the other side well with water as well - this helps the naan stick to the tawa.