Cut shrimp in half crosswise. In a large bowl, toss shrimp with 1 teaspoon kosher salt and baking soda. Refrigerate for 15 minutes or up to 1 hour.

• 1 pound (454 g) jumbo shell-on shrimp (16 to 20 count), peeled and deveined, shells reserved
• 1 teaspoon Diamond Crystal kosher salt, plus more to taste; for table salt, use half as much by volume
• 1/4 teaspoon baking soda