In a large bowl, stir together the warm water and yeast. Let stand for 10 minutes to activate the yeast.
Make the dough:
In the bowl of your stand mixer, combine the flour, salt, and brown sugar. Turn the mixer on low, and add the softened butter and activated yeast. Scrape the sides a few times to combine.
Switch the attachment to the bread hook and mix for another 5 minutes, dusting with a little more flour along the way to make sure it doesn’t stick to the sides of the bowl.
Let it rest:
Once the dough is elastic, remove it from the mixing bowl, and shape it into a ball. Transfer it to a lightly greased bowl and turn to coat with oil. Cover with a kitchen towel and let it rest overnight or 2-3 hours in a warm spot.
Prep for cooking:
Position one oven rack on the upper shelf and a second on the lower shelf. Preheat oven to 450F and generously grease 2 large baking sheets.
In a 5-quart saucepan, bring the water and baking soda to a boil.
Punch the down dough and divide into quarters. Form each quarter of dough into 4 balls. Roll each ball into a 12-inch long rope. Cut each rope into 6 2-inch pieces.
Cook:
Place a dozen pretzel bites into the boiling water and boil for 30 seconds. Using a slotted spoon, transfer onto the greased baking sheets.
Bake the pretzel bites in the preheated oven, switching baking sheets between racks and rotating the baking sheets halfway through baking, until browned, 8 to 10 minutes (watch closely toward the end of baking; bites brown quickly in the last few minutes). Immediately transfer pretzel bites to wire racks to cool.
Coat with cinnamon:
In a small bowl, combine the sugar and cinnamon. Brush the pretzel bites with melted butter and lightly dip into the cinnamon-sugar mixture.