Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
   2      packages      active dry yeast
   2      cups          water
     1/2  cup           sugar
     1/4  cup           unsalted butter
   1                    egg
   2      teaspoons     salt
   7      cups          flour
   1                    egg yolk
   1      tablespoon    water
   1      tablespoon    kosher salt
     1/4  cup           mustard

Preparation:

COMBINE YEAST, WATER, AND SUGAR IN A LARGE MIXING BOWL-MIX WELL.~ ADD BUTTER, EGG, SALT, AND 3 CUPS FLOUR-MIX UNTIL SMOOTH CONTINUE TO MIX IN. FLOUR UNTIL MIXTURE STIFFENS. ROLL INTO A BALL OR LOG. WRAP IN PLASTIC AND CHILL FOR 4-24 HOURS. DIVIDE DOUGH INTO 36 PORTIONS. ROLL EACH PIECE INTO AN 18-INCH ROPE. FORM INTO A PRETZEL SHAPE, PRESSING ENDS TO SEAL. PLACE ONTO A PARCHMENT-LINED BAKING SHEET. REPEAT WITH REMAINING DOUGH. COMBINE YOLK AND WATER-MIX WELL. BRUSH OVER PRETZELS. COVER AND ALLOW TO RISE FOR 30-45 MINUTES. BAKE @ 400 DEGREES FOR 10-15 MINUTES. DIP IN SALT AS DESIRED. SERVE WARM, WITH MUSTARD TO THE SIDE.