How to Make It
In the bowl of a standing electric mixer fitted with the dough hook, combine the 3 3/4 cups of bread flour with the warm water, yeast, kosher salt and butter and knead at medium speed until the flour is evenly moistened, 2 minutes. Increase the speed to high and knead until a smooth, elastic dough forms around the hook, 8 minutes.
Transfer the dough to a lightly floured surface. Cover loosely with a dry kitchen towel and let rest for 5 minutes. Cut the dough into 8 equal pieces and form each one into a ball. Cover the dough balls with the towel and let rest for another 5 minutes.
On an unfloured surface, roll each ball of dough into an 18-inch-long rope, tapering them slightly at both ends. To shape each pretzel, form the rope into a U shape. Cross the ends over each other twice to form the twist, then bring the ends to the bottom of the U and press the tips onto it. Arrange the pretzels on 2 large baking sheets lined with parchment paper and let stand uncovered in a warm place for 45 minutes, or until slightly risen. Refrigerate the pretzels uncovered for at least 2 hours or overnight.
Preheat the oven to 400°. While wearing latex gloves, long sleeves and safety goggles, fill a large, deep ceramic, plastic or glass bowl with the lukewarm water. Carefully add the lye (always be sure to add lye to water, never the other way around) and, taking care not to splash, stir the solution occasionally until all the beads have fully dissolved, about 5 minutes. Using a slotted spatula, gently lower a pretzel into the solution for 15 seconds. Carefully turn the pretzel over and soak it for another 15 seconds. With the spatula, remove the pretzel from the lye solution and return it to the baking sheets.
Sprinkle the pretzels with coarse salt and bake on the top and middle racks of the oven until shiny-brown and risen, about 17 minutes; shift the pans halfway through baking. Let the pretzels cool slightly on the baking sheets before serving.
Food-grade lye can be ordered from essentialdepot.com. Coarse salt and pretzel salt can be found at specialty-food stores or online at americanspice.com.
Lye Alternative: To make a lye alternative, dissolve 1/2 cup baking soda in 2 quarts of boiling water. Boil the pretzels for 30 seconds, then drain on wire racks before salting and baking.