Line half sheet pans with parchment paper and spray with vegetable spray.
Combine the milk, sugar, yeast, and butter in the bowl of a stand mixer and mix with the dough hook until combined. Let sit for 5 minutes, or until bubbly.
Add the salt and flour and mix on low speed until combined. Increase the speed to medium and continue kneading until the dough is smooth and begins to pull away from the side of the bowl, about 3 to 4 minutes. If the dough does not pull away from the sides of the bowl, it is too wet, add additional flour, 1 tablespoon at a time, until it starts to pull away from the sides. Continue to knead the dough for 4more minutes until soft.
Oil a bowl with vegetable oil, add the dough and coat with the oil. Cover with plastic wrap and place in a warm spot until the dough doubles in size, about 1 hour.
Preheat the oven to 425 degrees F.
Bring the 3 quarts of water to a boil in a small roasting pan over high heat and add the baking soda.
Remove the dough from the bowl. Turn the dough out onto a lightly-oiled surface, and roll into a 10x20-inch rectangle.
Cut the dough into 18 1-inch wide strips, then twist into a pretzel shape pinching the edges to seal.
Dip 2 or 3 pretzels into the warm baking soda water for 1 - 2 seconds. Remove from the water.
Arrange the pretzels on the prepared baking sheets. Brush each pretzel with the egg yolk mixture, and add your favorite toppings.
Bake in the preheated oven until golden brown, about 15 minutes. Allow to cool for 5 minutes and enjoy.