In a large bowl, combine the yeast with 1 1/2 cups warm water and stir to dissolve. Add sugar and salt and stir to dissolve. Add the flour, one cup at a time, until combined. Dump the dough onto a floured surface and knead 5 minutes until smooth. Place dough into a buttered bowl, cover with a damp towel and allow to rise at least 30 minutes.

In a shallow baking dish, combine 2 cups warm water with the baking soda. Stir well. Line a baking sheet with parchment paper.

Pinch off bits of dough and roll into long, thin ropes and form into pretzel shapes. Keep the dough covered during this process, except for the parts you're working with. Dip pretzels in the water bath and place onto the parchment-lined baking sheet. Allow to rise on the baking sheet for another 20 minutes.