Take a small bowl, put 50 ml. water, yeast and sugar and leave it aside for 10 min.
Take a broad bowl, put weissmehl and salt and mix it with a fork.
Add yeast mix and yogurt and start mixing the dough.
Slowly add water and knead the dough.
If the dough is too sticky, add a little dry weissmehl and knead it further.
Transfer it to a big bowl, cover it and let it grow until it has doubled the volume - at least 2 hours.
Start oven at the upper grill at 230 temp. Remove trays and put baking paper on it.
Put oil on dough and knead again till it has a nice texture.
Take kiwi size dough, make round and roll it flat.
Put it in the baking tray and once the oven is heated, put it inside the oven on very top to cook.
Change sides of the naan once it is cooked on top.
When both sides are done, remove it from the oven, spread butter and serve hot with your choice of curry.
Naan dough is very sticky and much softer than Pizza dough. It will get smoother consistancy only after it has grown doubled in volume and you have knead it again using oil. In the traditional recipes, naans are just streched out through palms without using rolling pin. So if at the beginning if the dough feels liquid, do not worry.
You can also try naan with different types of flours - but please remember that the quantity of water to knead will differ for different types of flours.