Place the water and wine in a large skillet over medium heat.
Bring the water to a boil and then reduce the heat until the water is at a shiver.
Gently add the chicken thighs and poach for about 10 – 15 minutes depending on the thickness (It’s best to use an instant thermometer and remove the thighs just as they reach 160°F.)
Remove from the water and let the chicken rest for 3 – 5 minutes.
When the chicken is cool, cut the thighs into 1/2 inch cubes. Chill in the refrigerator for about 30 minutes.
Remove from the fridge and add the diced celery, garlic, mayonnaise, salt and pepper.
Fold the salad together gently and chill for another 15 minutes before serving.
To serve:
For each sandwich, spread 1/2 cup salad on a slice of whole grain bread.
Add a slice of tomato and a leaf of lettuce, if desired.
Top with a second slice of whole grain bread and serve.
