Heat oven to 425ºF. Place racks on lowest and highest positions in oven. Fill Dutch oven with 10 cups water. Add baking soda; stir until dissolved. Bring water just to simmer. Carefully add 6 pretzel twists, 1 at a time, to hot water; cook 1-1/2 min. or until pretzels start to puff, turning after 45 sec. Remove pretzels from water with slotted spatula; return to baking sheet. Repeat with remaining pretzel twists, using both baking sheets. Sprinkle with remaining salt. Place 1 baking sheet on each oven rack.