Sprinkle yeast on 1 1/2 cups warm water, stir to dissolve. Let sit for 10 minutes to activate yeast.
Add sugar and salt, stir to dissolve.
Add flours and knead dough until smooth and elastic.
Put in a warm place and let rise for at least 30 minutes or until doubled in size.
After dough has risen, divide into 12 equal pieces and roll into a long, thin rope. At least 24 inches long, longer up to 36 inches if possible. Shape into pretzels. (form a U then cross over, twist, and bring to bottom.)
Prepare a baking soda bath with the remaining water and baking soda.
Dip each pretzel into baking soda bath for a few seconds before putting onto a greased baking sheet. Sprinkle with coarse salt, if desired.
Bake at 450 for 10-15 minutes or until golden brown.
Brush with melted butter immediately after removing from oven.