COMBINE all the dressing ingredients in a small mixing bowl and whisk until well incorporated.
POUR 1/4 cup of dressing in the bottom of 4 (quart-sized) mason jars.
LAYER 1/4 cup of celery, 1/4 cup of red onion, a handful of cherry tomatoes, 1/2 cup cucumber and 6-7 shrimp in each jar. Fill the jars to the top with romaine lettuce, packing it in tightly.
COVER the jars and store in the refrigerator for up to 4 days.