Preheat oven to 350 degrees F. Preheat a grill pan.
Chicken Salad: Season both sides of the chicken breast with salt, pepper, and a little oil. Place on the grill for approximately 2 1/2 minutes on each side, remove from the grill and place in the oven to finish the cooking process. When the chicken is fully cooked, approximately 12 minutes, place in the refrigerator to cool. After the chicken has cooled, dice it in small bite size pieces and place in a stainless steel bowl with the 1/2 cup mayonnaise, chopped truffle, and truffle oil. Mix well and reserve for later use.
Spread a small amount of mayonnaise onto 2 slices of the sour dough bread. On 1 of the slices with mayonnaise place the following items; Boston lettuce, 2 slices of tomato, 3 slices cooked bacon, 3 slices avocado, and half of the bean sprouts, place the other slice of bread on top mayonnaise side down. Next place half of the reserved chicken salad on top of the dry side of bread and spread evenly, finish the sandwich with the last slice of dry bread and place in a panini press until toasted. Remove the sandwich from the press and cut in quarters. Repeat with remaining bread and fillings. Serve with French fries or potato chips.
Recipe courtesy of The Ritz-Carlton, Boston Common Jer-Ne Restaurant and Bar by Scott C. Gambone