Dissolve yeast in the lukewarm water. Mix flour and salt together in a large mixing bowl. Form a well in the flour mixture then add the sugar to the center of the well. Pour the yeast/water mixture into the well. Let it rest for 15 minutes before mixing.
Add the softened butter to the mixing bowl and knead everything to a smooth dough. I used the dough hook on my Kitchenaid for about 6 minutes on speed #2, I did have to add about a tablespoon of additional water as it was not quite gathering all the dry ingredients. Remove the dough hook and let the dough rest for 30 minutes.
Cut the dough into twelve equal parts, then roll each piece on the table (don't flour the surface, you shouldn't need it) to about 20 inches, tapered toward the ends. Don't make it smaller than 20 inches as it's impossible to get a good shape with a short, thick rope of dough. The dough should not get too warm as you roll it out, or it might tear.
To form the pretzel shape, place dough rope on parchment lined cookie sheet so that it creates the shape of the letter "U". Take both ends of the "U" and cross them over each other twice forming a twist. Bring that twist down and place it over the bottom curve of the "U".
Place the pretzels without covering them in the fridge for about an hour. This helps build a skin that will absorb the dipping solution better and make a beautiful shiny crust.
Preheat the oven to 400 F.
Fill large stock or pasta pot 3/4 full and bring the water to a boil. Carefully and slowly add the baking soda to the boiling water. There will be a reaction when the baking soda hits the water and it will bubble furiously for a moment and then relax. Stand back a bit just to be safe. Using a slotted spoon, gently drop each pretzel into the bath for 10 seconds, then turn over for another 10. Astrid called for a total of 10 seconds only. Place them on a baking sheet lined with parchment paper.
Score the dough once like for a baguette with a razor blade or sharp knife.
Sprinkle with coarse salt. Bake the pretzels for about 15 to 20 minutes (mine took 20 minutes for a nice dark crust), depending on how dark you like them.
An authentic German recipe calls for a lye solution, but baking soda is a perfectly acceptable and widely used substitute.