In a small cup, combine warm water, active dry yeast, and white sugar. Stir and let sit for 10 minutes until frothy.

In a large mixing bowl, whisk together all-purpose flour and salt. Pour in frothy yeast mixture and melted butter. Mix until dough forms.

Knead the dough for 6-7 minutes until smooth and elastic. Grease a bowl, place dough inside, cover, and let rise for 1 hour.

Punch down risen dough, divide into 8 pieces, and shape into balls. Place on a parchment-lined baking sheet and let rise for 20 minutes.

Preheat oven to 425°F. Boil water and baking soda in a pot. Boil each bun for 30 seconds on each side, then place back on baking sheet.

Score tops of buns with an 'X', sprinkle with sea salt, and bake for 20-22 minutes until golden brown. Let cool slightly before serving.