Proof yeast: Combine warm water with yeast and sugar. After 5 to 10 minutes, the mixture should be frothy.
Combine with flour: In a large bowl (or the bowl of your Kitchen Aid), combine flour and salt. Add yeast mixture and yogurt.
Knead: Knead by hand (8 minutes) or with the bread hook of a standing mixer (5 minutes at medium speed), until dough is smooth. The dough will be sticky, but if it is too sticky to handle, add flour 1 tablespoon at a time.
Rise: Place dough in a lightly greased bowl and cover with plastic wrap. Set in a warm place* and let rise for 1 to 2 hours, or until dough has doubled in size.
Divide: On a well-floured surface, flatten dough into a disk, then cut that disk into 8 pieces.
Cook: Heat a cast iron skillet or heavy-bottomed pan over medium/high heat. Working one at a time, roll each piece of naan on a floured surface to about 1/4 inch thick (it's fine if the shape isn't perfect). Cook in the skillet, about 2 minutes per side (until golden brown with slightly charred spots). Cover with a towel to keep warm while you finish the rest.
To make cheese naan cut the dough into 16 pieces (rather than 8). Roll each out to ⅛-inch. Sprinkle a few tablespoons of mozzarella cheese into the center, top with another piece, and crimp the edges to seal. Cook as instructed above.Store naan in an air tight container at room temp for a few days. To reheat, wrap in a damp paper towel and microwave for 15 seconds.