Preheat oven to 400 degrees F. Line two baking sheets with parchment paper and set aside. In a small bowl, whisk together 1.5 cups water and yeast. Let stand 5 minutes until yeast is bubbly.

In a large bowl, combine flour, brown sugar, and salt. Mix in egg yolk, butter, and yeast mixture. Stir in a  bowl until combined and then turn out on a floured surface and knead until the dough is a well-mixed, 5-7 minutes. Let dough rest for 5 minutes.

In a large shallow dish, combine the baking soda with 2 cups of warm water. On a work surface, divide the dough into six equal pieces. Using your hands, roll each piece into a 42" rope. Dip each rope or dough shape into the baking soda water for 30 seconds and then shape into a pretzel (Alternatively, you can make pretzel bites, smaller pretzels, or other shapes as desired).

In a small bowl, beat the egg water with 1 TBS water. Brush each pretzel with the egg wash. Sprinkle with coarse salt. Bake until deep golden, 12-15 minutes for the larger pretzels, 8-12 minutes for smaller pretzels.