In a stand mixer's bowl, add the sourdough starter, water, sugar, salt, and flour. Mix on the lowest speed for 5-10 minutes using the dough hook. The dough should smooth and elastic.
Add the dough to a greased bowl and cover with plastic wrap or a lid and let it rest at room temperature for 8-12 hours or until it doubles in size.
Divide the risen dough into 12. Roll each portion into an 14” - 18” rope and shape it into a U.
Twist the two ends of the rope twice and press them into the base of the U-shape.
Set pretzels aside to allow the shaped dough to rise for approximately an hour.
Preheat your oven to 425°F.
In a large stockpot, bring water to a boil and add 1 tablespoon each of baking soda and brown sugar.
Bath the pretzels for 30 seconds on each side, one or two at a time making sure they don’t touch.
Place the boiled pretzels on a parchment-lined baking sheet.
Brush each pretzel with an egg wash and sprinkle coarse salt on top.
Bake for 15 minutes or until they turn golden brown.
Enjoy with your favorite dipping sauce.