1. Mix flour, baking powder, sugar and salt in a bowl.
2. In a small saucepan, heat milk together with butter (in small pieces), until butter has melted. You can also do this in a microwave. Let the milk cool down slightly.
3. In a big bowl add yogurt and stir in warm (not hot!) milk until smooth.
4. Gradually, add the dry ingredients and stir with a spoon, until the ingredients come together.
5. With your hands, knead to a smooth dough. It’s best to first knead the dough in the bowl and later transfer to a lightly floured surface and keep kneading. If the dough is still sticky, add a little more flour.
6. Let the dough rest for ½ hour on a lightly-floured surface and put the empty bowl upside-down on top of it. Alternatively, let it rest in the bowl, covered with a lid or cling wrap. The longer the dough rests, the softer it gets and the easier it will roll out.
7. Split dough into 4 equal parts (it's best to use a kitchen scale), shape each into a ball and roll out.
8. Rotate the dough-disk while rolling, and flip it over occasionally. Sprinkle with flour every now and then, so it will not stick to your rolling pin or surface. When finished, the Naan should have an oval shape, 6’’ x 9’’ large and about 1/8 inch thick.
9. Preheat skillet or pan to medium high heat – but don’t add any oil.
10. Pick up the Naan, remove excess flour by slapping the dough between your hands and put it into the pan. Cook until bubbles have formed on top and the bottom side gets lightly nicely browned. Then flip, and cook until done, about 1 minute.
11. Wrap the ready Naans in a kitchen towel or place on a plate and cover with a kitchen towel or aluminum foil keeping them warm while baking the rest. That will also make the Naans really soft.
12. For Butter-Naan, brush each flatbread with melted butter, for Garlic-Butter-Naan rub bread with garlic cloves first and then brush them with butter. Enjoy!