In a large bowl, whisk together instant yeast and warm water. Let the yeast activate (1 minute rest) and add salt, brown sugar, and butter.
Periodically add in 3 cups of flour, and mix with a spoon until a thick dough forms. Add remaining flour until the dough is not sticky. Check dough by pressing your finger and seeing if the dough bounces back.
Flour your counter, place dough and knead for 3 minutes. Shape the dough into a ball and cover the bowl with a towel and rest for 10 minutes.
Preheat oven to 400°F. On 2 baking sheets, place parchment paper with nonstick spray
In a pot, add water and baking soda and heat to boil.
Cut dough into 3 sections with a pizza cutter. Roll each piece of dough into a 22 inch rope. Form a circle by placing the end pieces together and twist the ends. With the twisted end, bring it down the opposite end and press it onto the dough.
In the boiling pot, drop 1 pretzel into the boiling water for 30 seconds. Use a spatula to push lift the pretzel out and place onto the baking sheet. Sprinkle with coarse sea salt. Repeat for remaining pretzels.
Bake in oven for 14 minutes or until the pretzel turns golden brown.
Remove and let is rest for 3 minutes. Serve.