Using a fork, combine the bread flour, sugar, salt, yeast and water into a shaggy dough in the bottom of your stand mixer bowl.
Fit the dough hook and set the mixer to a low speed. Gradually add the butter until it is all incorporated into the dough, scraping down the sides with a rubber spatula if needed.
Turn the speed up to high and knead the dough for 5 minutes. Then, leave it covered to rest for 30 minutes.
Wet your hand under the cold tap, then use it to lift the dough from the side of the bowl and fold it in on itself. Repeat, turning the bowl slightly each time, until the dough has formed a smooth, tight ball and has too much resistance in it for you to continue. Cover the dough again and rest for a further 30 minutes.
Turn the dough out onto a clean surface and divide into 10 equal pieces. The dough should not stick to the countertop, but if you’re having problems use oil not flour on the countertop.
Roll each piece into a long, roughly 20” sausage, letting the ends taper a little but keeping the middle still relatively thick. After you’ve rolled each one, shape the pretzel and transfer to a light oiled tray that will fit in your refrigerator (use multiples if needed.)
To shape, lift the ends above the middle of the sausage of dough, and twist twice to create a loop. Then, fold the twist downwards so it rests in the middle of the loop, securing the two ends on the middle of the pretzel.
Cover the shaped pretzels with oiled food wrap and leave to rest at room temperature for 30 minutes before transferring to the refrigerator for 1 hour to chill.
Heat the oven to 450F and line two large baking sheets with baking parchment.
Boil 6 cups of water in a large pan, and add the baking soda. It should froth when it hits the water.
Boil the pretzels for 1 minute at a time, without turning, working in batches of 3. As you lift the pretzels off of the sheet to add them to the water, stretch them out a little to get a better pretzel-like shape. Remove them from the water with a slotted spoon and transfer them to the prepared baking sheets.
Sprinkle the pretzels with salt before baking for 15 minutes until cooked through and golden.