In the bowl of a stand mixer, combine the water, sugar and kosher salt. Sprinkle the yeast on top and leave it for five minutes or until the mixture begins to foam. Add the flour and butter and, using the dough hook attachment, mix on low speed until well combined. Change to medium speed and knead until the dough is smooth and pulls away from the side of the bowl, approximately four to five minutes.

Remove the dough from the bowl, clean it, and then coat the inside of the bowl vegetable oil. Return the dough to the bowl, cover with plastic wrap and place it in a warm place for approximately 50 to 55 minutes, or until the dough has doubled in size.

Preheat the oven to 450° F (232°C). Line 2 half-sheet pans with parchment paper and lightly brush them with vegetable oil. Combine the water and baking soda in an 8-quart pot and bring it to a rolling boil over high heat.

While the water comes to boil prepare the dough by first transferring it to a work surface coated lightly with oil. Divide the dough into eight equal pieces (or 16 if you want smaller pretzels). Roll out each piece of dough into a 24-inch rope (12 inches for smaller pretzels). Make a U-shape with the rope and, holding the ends of the rope, cross them over each other and press onto the bottom of the U in order to form the shape of a pretzel. Place them on the parchment-lined half sheet pan.

Boil the pretzels, one at a time, for 30 seconds. Remove them from the water using a large flat spatula and transfer them back to the sheet pan. Repeat with the rest of the pretzels.

Brush the top of each pretzel with the egg wash and sprinkle with the pretzel salt, if using. Bake the pretzels for twelve minutes (or six to seven minutes for small pretzels), or until they golden brown.  Transfer to a cooling rack for five minutes before serving.