Combine yeast, warm water and sugar in the bowl of a stand mixer fitted with a hook attachment. Mix the mixture until the yeast starts to become bubbly. Mix in the salt and melted butter. Add in 1 cup of flour until mixed, continue with the rest of the flour mixing in 1 cup at a time until the dough is not sticky. More flour may need to be added as necessary.
Knead the dough for 5 minutes and form into a ball. Place the dough back in the bowl and let rest for 15 minutes.
While the dough is resting, prepare the baking soda bath. In a sauce pan, boil 2 cups of water along with the baking soda. After the baking soda is dissolved, remove the mixture from the heat and pour into a 9x9 pan.
Once the baking soda bath is prepared, the dough should be finished resting. Remove the dough from the bowl and cut into 8 sections. Roll each section into a rope about 19-20 inches long (I roll the dough between my hands). Shape the long rope into a pretzel and place into the baking soda bath for 2 minutes. Place onto baking sheet. Continue rolling and shaping the other pretzels and placing in the baking soda bath until all of the pretzels are prepared.
Bake the pretzels for 8-9 minutes or until they are golden brown. After removing from the oven, brush generously with the melted butter.