In a large mixing bowl, add mayonnaise, lemon juice, and Dijon mustard. Whisk these ingredients together until smooth and well combined.

Take the imitation crab meat and break it into bite-sized chunks, then gently fold it into the dressing using a spatula.

Finely dice celery stalks, and mince red onion. Add the chopped vegetables along with corn kernels to the crab mixture, stirring carefully.

Sprinkle salt and pepper to taste, adjusting flavors. Mix lightly, and add dill if desired.

Cover the bowl with plastic wrap and refrigerate for at least 30 minutes, ideally 1 hour to meld the flavors.

Once chilled, serve the salad over crisp lettuce leaves or as a filling for sandwiches or with crackers.