Bloom the Yeast:

Warm 1/3 cup water to 110-120°F (43-49°C) in a microwave-safe bowl, roughly 1 minute. Add the yeast packet and 1 tablespoon sugar; stir until dissolved. Allow to sit for 5 minutes until frothy.

Knead the Dough:

In a stand mixer bowl with the dough hook, combine the room-temperature milk, 3 tablespoons melted butter, eggs, and kosher salt. Using a silicone spatula, mix in half the flour, then add the remaining flour and the bloomed yeast. Knead on low-medium speed for 4-5 minutes until a smooth dough forms. If too sticky, dust in a little extra flour.

First Rise:

Coat a large bowl with 1 tablespoon butter. Place the dough ball inside, turning to coat all sides. Cover with a towel or plastic wrap and let rise in a warm spot for 90 minutes until doubled in size.

Divide the Dough:

Deflate the dough. Lightly dust a clean work surface with flour and gently flatten the dough into a circle. Using a bench scraper or a sharp knife, divide into 12 equal portions.

Shape and Second Rise:

Form each piece into a ball by folding the edges inward and pinching the bottom. Grease a 10-inch cast iron skillet with 1 tablespoon butter. Arrange the dough balls seam-side down in the skillet, side by side. Cover and let rise for 1 hour until puffy and touching.

Preheat Oven:

Preheat the oven to 375°F (190°C).

Brush with Butter:

Brush the tops and gaps of the rolls with 1 tablespoon melted butter.

Bake Rolls:

Bake for 20-25 minutes, turning the skillet halfway, until golden brown.

Make Garlic Butter:

While baking, prepare the garlic herb butter: whisk together 3 tablespoons melted butter, minced garlic, and parsley.

Finish with Garlic Butter:

Take the rolls out of the oven. Immediately brush with the garlic herb butter. Grate fresh Parmesan over the top and sprinkle with flaky sea salt.

Serve Warm:

Serve warm. Use a spatula to lift the entire roll cluster onto a plate; pull apart to reveal the soft interiors.