In a large measuring cup combine the water and 1 teaspoon of sugar. Add the yeast and set aside until frothy, about 10 minutes.
Sift together the flour, salt and remaining sugar in a large bowl.
Once the yeast is bloomed and bubbly add the milk and oil stirring gently to combine. Add the egg yolk and whisk until blended. Pour the milk and yeast mixture into the dry ingredients. Mix with a fork just until incorporated. Once the dough starts to come together, start mixing with you hands. The dough will seem a little wet but keep folding and working it until you have a soft, slightly sticky, pliable dough. Cover the bowl with plastic wrap or a damp tea bowl and let rise for 1 to 2 hours or until doubled in size.
Lightly oil a small baking sheet and set aside.
Turn out the dough onto a lightly floured work surface. Divide into 6 equal pieces and shape each into a smooth, tight ball. Place the dough balls on the prepared baking sheet at least 2-inches apart. Lightly coat a piece of plastic wrap with vegetable cooking spray. Cover the dough loosely with the plastic wrap, oil side down. Set aside for 15 to 20 minutes while preheating the pan.
Heat the remaining two tablespoons of butter until melted. Add the parsley or cilantro and stir to combine. Set aside.
Warm a cast iron skillet over medium high heat. Add 1 teaspoon of oil and heat until shimmering. Carefully wipe the oil out of the skillet with paper towels.
Lightly coat the work surface with flour again. Using your hands and a rolling pin, press and roll each piece of dough into a 6 to 9-inch round depending how thick you prefer the naan. Dampen your hands lightly with water. Flip-flop naan from one hand to the other to lightly dampen the surface on both sides. Alternately use a clean water sprayer or mister. Spray one side, place wet side down in the skillet, then mist the top.
Cover the skillet and cook until the bottom of the Naan in browned in spots, about 2 to 4 minutes. Flip the naan, cover and continue cooking until lightly browned, 2 to 3 minutes more. If the naan puffs up, gently deflate the bubble with a fork or the tip of a small, sharp knife. Once browned, flip the naan one last time and brush the top with melted butter. Transfer to a baking pan, cover and keep warm.
Repeat rolling and cooking the remaining 5 dough balls. Serve immediately.