Cook the beef strips in a skillet over medium heat until crispy, then crumble them into bite-sized pieces.

In a large bowl, combine the shredded chicken breast, halved cherry tomatoes, diced celery, red onion, and chopped crispy beef.

Fold the mayonnaise and fresh parsley into the mixture until all ingredients are evenly coated.

Slice the croissants in half and generously scoop the filling onto the bottom half of each before serving.