How to Make It
Stir together cucumbers, bell peppers, onion, serrano peppers, garlic, and kosher salt in a large bowl. Stir together vinegar, sugar, sesame seeds, mustard seeds, and celery seeds in a small bowl. Let both mixtures stand, stirring occasionally, 1 hour. Drain cucumber mixture. (Do not rinse.) Pour vinegar mixture over cucumber mixture; stir to coat. Chill 2 to 24 hours. Serve with a slotted spoon.