In a large bowl, flake the drained tuna with a fork.
Add chopped eggs, celery (if using), relish, diced apple, and dill.
Sprinkle in Veteran's Blackened Seasoning, Old Bay, salt, and black pepper.
Add mayonnaise and gently mix until everything is well combined.
Taste and adjust seasonings as needed.
Chill in the fridge for at least
30 minutes for best flavor.
Spoon tuna mixture onto buttery croissants. Add lettuce if using.
Serve chilled and enjoy!