If you want to flavour the pretzels, sprinkle with a little cumin seeds or caraway seeds before they are baked in the oven. Makes 8 large pretzels.
Add warm water to the bowl of a stand mixer, sprinkle the yeast over the water. Let sit for 5 minutes or until foaming.
Sift together the 1½ cups flour with the sugar and salt onto parchment paper or a medium bowl. Add flour mixture and butter to yeast mixture in the stand mixer. Mix dough in the stand mixer fitted with a dough hook on medium speed about 3 to 5 minutes. If necessary, with a spatula, scrape down the sides of the bowl to incorporate all the flour. Sift 1 cup flour, add to dough and mix in. If the dough is still really sticky, add remaining ¼ cup flour.
Transfer dough to a lightly floured work surface and knead by hand so that the dough is no longer sticky. Place dough in a lightly oiled large bowl. Cover with saran wrap. Place dough in a warm place. Let rise until doubled in size, about 1 hour.
Line 2 baking sheets with parchment paper.
Punch down the dough and divide it into eight equal pieces. Roll out each piece with the palms of your hands until the piece is approximately 22-inches long. Form each long piece into a pretzel shape or leave shape and make pretzel sticks.
Transfer pretzels to prepared baking sheets leaving 1 1/2-inch space between pretzels, that is, about 4 pretzels per baking sheet. Place in a warm place and let rise until doubled in size, about 30 minutes.
Preheat the oven to 475 degrees F.
In a large non-reactive pot, bring water and baking soda to a boil.
Carefully add 4 pretzels, right side up, in the boiling baking soda solution with a slotted spoon. Flip the pretzel over. The pretzels are only in the solution for about 20 seconds total time. Carefully transfer pretzels back to baking sheet, right side, spacing again apart and 4 per sheet. Sprinkle each one generously with coarse sea salt. Repeat with cooking process with 4 remaining pretzels.
Bake in oven until the pretzels are crispy and brown, about 10 to 12 minutes. Remove from oven and let cool briefly before eating. Serve with mustard if desired.