In a large bowl, whisk together the flour, yeast, sugar, and salt. Make a well in the center and add the warm water, yogurt, and olive oil. Mix with a wooden spoon until a shaggy dough forms. The dough will be sticky - that's perfect.
Cover the bowl with plastic wrap or a clean kitchen towel and let it rise in a warm place for 1-2 hours, or until doubled in size. I usually find a spot near the oven or on top of the refrigerator works well.
After the dough has risen, turn it out onto a lightly floured surface. Divide into 8 equal pieces. Roll each piece into a ball, then cover with a towel and let rest for 15 minutes. This relaxes the gluten and makes rolling easier.
Heat a heavy skillet or cast iron pan over medium-high heat. While the pan heats, roll each ball into an oval or round shape about ¼ inch thick. Don't worry about perfect shapes - rustic is beautiful.
Cook each naan for 2-3 minutes per side, or until puffed up with golden brown spots. You should see bubbles forming on the surface. If you have a gas stove, you can carefully hold the naan over the flame with tongs for extra charring.
Brush the hot naan with melted butter (mixed with minced garlic if making garlic naan) and sprinkle with cilantro if using. Serve immediately while warm and soft.
