Prepare all of the ingrients. Start water boiling for shrimp.
Add half of lemon juice to boiling water. Add raw shrimp to boiling water. Let cook for 4 minutes (should be juice pink). Drain into colander and rinse with cool water.
Roughly chop shrimp into ½ inch pieces, Set aside to let cool completley.
Combine yogurt, garlic, dill, remaining lemon juice, lemon zest, mustard, honey and old bay seasoning.
Add cucumber, onion, celery, and chopped shrimp to a bowl. Pour yogurt mix over and toss to coat.
Serve between two halves of the croissant with a piece of green leaf on the bottom half.