2) When the chicken is cool, remove and discard the skin and bones and cut the chicken into 2cm dice. Place the chicken in a bowl and add the mayonnaise, tarragon, celery, 2 tsp of salt, and 1 tsp pepper. Toss well.
3) To assemble, spread a little mayonnaise on half the bread slices, top with the chicken and green salad mix, and cover with the remaining slices of bread. Cut in half and serve.