Whisk together water, yeast and sugar in the bowl of a stand mixer. Allow the mixture to proof for 5 minutes.
While the yeast is proofing, whisk together the flour and salt in a separate bowl.
Attach the dough hook to the stand mixer. Add the flour mixture to the yeast mixture. Mix on low speed until the dough comes together and then turn the speed up to medium-low and knead for 3 minutes. Turn the speed up to medium and knead for another 2 minutes.
Form the dough into a tight ball and place into a lightly greased bowl. Cover with a clean kitchen towel and allow the dough to double in size, approximately 40 minutes. Remove the towel and punch down the dough.
Lightly grease a baking sheet. Divide the dough into eight equal parts. Roll each piece tightly into a smooth ball and pinch the bottoms. Place the balls pinched side down on the baking sheet, cover with a towel and allow the dough to rise for 20 minutes.
Preheat the oven to 425°F. Bring the 4 quarts of water to a boil with the baking soda. In batches, cook the rolls for 30 seconds per side. Remove with a slotted spoon and place onto a clean, greased baking sheet (do not use parchment paper or the rolls will stick).
Whisk together the egg with a tablespoon of water. Brush the egg wash on top of each roll and sprinkle generously with coarse sea salt.
Using a sharp knife, slice an X in the top of each roll (optional).
Bake for 15-17 minutes or until golden brown on top.