Proof the yeast in the bowl of a stand mixer by adding the yeast, 1 1/2 cups water and sugar together. Cover with a towel and let it stand for 5-10 minutes until bubbles form.
Add 3 TBSP of oil and salt. Using the dough hook, add in the flour a cup at a time on low speed until combined. Increase the speed to medium and knead the dough until the dough is smooth and pulls away from the sides of the bowl, about 4 minutes.
Remove the dough from the bowl and pour remaining 1 TBSP oil into the same bowl. Form the dough into a ball and place it back into the bowl. Turn to coat with oil. Cover with a towel or plastic wrap and place in a warm place for 1 hour or until double in size.
Preheat oven to 425 degrees. In a large pot bring the 8 cups of water.
Using a knife or pizza cutter, divide the dough into 8 equal pieces. Roll one piece into a large rope and *twist into a pretzel. Pinch the ends to the bottom of the pretzel. Repeat with remaining pieces. Add the baking soda to the boiling water and give it a little stir. Boil the pretzels, two at a time in the water solution for 45 seconds. Drain with a slotted spoon and place onto a parchment lined baking sheet.
Once all boiled, beat together egg and 1 TBSP water and brush over the tops. Generously sprinkle with salt. Bake for 16-20 minutes or until golden brown. Remove from oven and immediately brush with melted butter. Serve warm.