Activate the yeast by mixing warm water, sugar, and yeast in a large bowl; let sit 5 minutes until foamy.

Stir in flour and salt until a dough forms, then knead on a lightly floured surface for about 5 minutes until smooth and elastic, adding flour 1 tablespoon at a time if sticky.

Place dough in a greased bowl, cover with a damp cloth, and let rise in a warm spot until doubled in size, about 1 hour.

Preheat the oven to 450°F (232°C). Punch down the dough, divide into equal pieces, roll each into a 24-inch rope, and twist into pretzel shapes.

Bring water and baking soda to a gentle boil in a large pot; boil each pretzel for 30 seconds.

Transfer to a parchment-lined baking sheet, sprinkle with coarse salt, and bake for 12–15 minutes until golden brown.

Cool slightly on a wire rack before serving.