Sieve the flour into a bowl. Form a well in the flour and add the salt into it. Cut up the butter into small pieces and put it around the well.
Stir the yeast and sugar into the warm water. When everything is dissolved completely, pour the mixture into the flour, slightly mix some flour with the water mixture. Cover the bowl and let it rest for 15 minutes.
Knead the dough until it’s smooth, for about 10 minutes.
Divide the dough into 16 or 8 parts, depending on whether you want small or big pretzels. Cover the pieces and let them rest for another 20 minutes.
Preheat the oven to 180°C (360°F).
Shape the pretzels.
Bring 1l of water to a boil and add the baking soda. Boil the formed pretzels in the lye for 30 seconds, one at a time. Place them immediately on a baking tray lined with parchment paper.
Make a cut in the thicker part of the pretzel and put some coarse salt on it.
Bake for 15-20 minutes.