In a small bowl, combine warm water, yeast, and sugar. Let stand 5-10 minutes until foamy on top. If it does not foam, your yeast is dead and you need to start over.

In a large bowl, whisk together flour and salt. Add the yeast mixture, yogurt, and olive oil. Stir with a wooden spoon until a shaggy dough forms, then turn out onto a lightly floured surface and knead for 8-10 minutes until smooth and elastic. The dough should feel tacky but not sticky.

Lightly oil a clean bowl, place dough inside, and turn to coat. Cover with a damp kitchen towel and let rise in a warm spot for 1 to 1.5 hours until doubled in size. A slightly warm oven with the light on works perfectly.

Punch down the dough and turn out onto a lightly floured surface. Divide into 8 equal pieces and roll each into a ball. Cover with the damp towel and let rest 15 minutes. This relaxes the gluten so the naan will stretch properly.

Working one at a time, roll each ball into an oval or teardrop about 8 inches long and 1/4 inch thick. Do not roll too thin or the naan will be cracker-like. Keep remaining dough covered as you work.

Heat your cast iron skillet over medium-high heat until very hot, about 3 minutes. Working with one piece at a time, brush off excess flour and lay the naan in the dry skillet. Cook 1-2 minutes until large bubbles form on top and the bottom is blistered and deeply golden in spots. Flip and cook 1 minute more. The second side will not color as much. Transfer to a plate and cover loosely with foil while you cook the rest.

Melt butter in a small pan over medium heat. Add minced garlic and cook 30 seconds until fragrant but not browned. Brush garlic butter generously over each warm naan and sprinkle with cilantro. Serve immediately while soft and pliable.