In a large bowl, mix warm water and yeast. Let sit for 5 minutes until frothy.
Add salt, sugar, and flour. Knead the dough until smooth and elastic, about 5-7 minutes.
Cover and let the dough rise for 1 hour in a warm place.
Preheat the oven to 450°F and line baking sheets with parchment paper.
Bring 10 cups of water and baking soda to a boil in a large pot.
Divide dough into 8 pieces. Roll each into a rope and shape into pretzels.
Dip each pretzel in the baking soda solution for 30 seconds, then place on baking sheet.
Brush with beaten egg and sprinkle with coarse salt.
Bake for 12-15 minutes, or until golden brown. Let cool before serving.