Tear or chop the chicken into small pieces and put in a bowl.
Add the tarragon, mayonnaise and crème fraîche. Season with salt and pepper and squeeze in the lemon juice.
Fill the rolls with the chicken and mayonnaise mixture. If using regular-sized rolls, cut them into 4 to serve.
For top tips on protecting you and your family when preparing raw meat and poultry, visit Food Safety in the Home.