In a large mixing bowl, combine warm water, sugar, and yeast. Stir lightly and let it sit for about 5-10 minutes until frothy.
Add salt and flour, one cup at a time, mixing with a wooden spoon until a shaggy dough forms. Knead the dough in the bowl or on a floured surface until smooth and elastic.
Place in a lightly oiled bowl, cover, and let rise in a warm area for about an hour until doubled in size.
In a large pot, bring 10 cups of water to a boil and stir in baking soda.
Punch dough down, divide into 12 pieces, roll each into a ball, and make indents for grooves.
Place each pretzel into the boiling baking soda bath for about 30 seconds, turning once. Remove with a slotted spoon and place on a baking sheet lined with parchment paper.
Brush each pretzel with the beaten egg and sprinkle a bit of sea salt on top.
Preheat oven to 425°F (220°C) and bake the pretzels for 15-18 minutes until golden brown.
Allow to cool and garnish with optional ingredients before serving.
