In a small bowl, combine the warm water and sugar. Sprinkle the active dry yeast on top and let it sit for about 5-10 minutes, or until it becomes frothy.
In a large mixing bowl, combine the all-purpose flour and salt. Make a well in the center and add the activated yeast mixture, Greek yogurt, and vegetable oil. Mix until a shaggy dough forms.
Transfer the dough to a floured surface and knead for about 5-7 minutes, or until smooth and elastic. Form the dough into a ball, place in a lightly greased bowl, cover with a damp cloth, and let rise for 1-2 hours until doubled.
Punch down the dough to release air bubbles. Divide into 6-8 equal pieces. Roll each piece on a floured surface into an oval or teardrop shape about 1/4 inch thick.
Sprinkle the minced garlic and chopped cilantro over the rolled-out dough and gently press them in with the rolling pin.
Heat a skillet or tawa over medium-high heat and lightly grease with oil. Cook each naan for 1-2 minutes until bubbles form, flip and cook another 1-2 minutes until golden and slightly charred.
Remove the cooked naan and immediately brush with melted butter. Serve warm and enjoy.