Prepare The Chicken: Cook the chicken breasts and shred them. The chicken can be baked, grilled, or boiled according to your tastes.
Make The Dressing: Combine the mayonnaise, sour cream, white vinegar, salt, pepper, and dill in a mixing bowl. Mix until smooth.
Combine Ingredients: Add the shredded chicken, diced celery, and chopped green onions to the dressing. Gently fold them in until they are well coated with the dressing.
Chill: For the best flavor, refrigerate the chicken salad overnight or overnight. This enables the tastes to combine.
Serve: When ready to serve, scoop the chicken salad onto croissants.