Dijon Mayonnaise: In a mixing bowl, combine mayonnaise and Dijon mustard. Mix until well blended. Keep refrigerated until ready to use.
Roasted Peaches: Cut 2 peaches in half and remove pits. Place lemon juice in a bowl and add peaches. Toss gently until peach halves are completely coated. Add 1¼ teaspoons sugar to the bowl. Toss to evenly coat. Place peach halves, cut side up, onto a greased sheet tray. Place in a 425°F oven. Roast for 15 to 20 minutes or until peaches are soft, but still a little firm. Cool quickly under refrigeration. Once cooled, slice roasted peaches into ¼-inch to ½-inch slices. Keep refrigerated until ready to use.
Maple Marinade for Chicken: In a mixing bowl, combine water, apple cider, maple syrup and salt. Mix until well blended. Keep refrigerated until ready to use. Stir well before each use.
Maple Roasted Chicken Breast: Trim all fat from chicken. Using a meat tenderizer or mallet, gently pound each chicken breast. Place chicken in a large mixing bowl. Pour maple marinade over meat to evenly coat. Keep refrigerated for 8 hours to marinate. Drain and discard excess sauce before cooking. Preheat oven to 425°F. Place chicken in a large roasting pan. Cook for 6 to 8 minutes. Turn chicken over. Cook for another 7 to 8 minutes or until minimum internal temperature is 165°F. Cool quickly under refrigeration. Keep refrigerated until ready to use.
Toast each slice of bread.
Sandwich Build: For each sandwich, place 1 slice multigrain toast on a flat work surface. Spread 1 tablespoon Dijon mayonnaise on one slice of toasted bread. Place 2 tablespoons goat cheese on bread. Place 1 leaf green lettuce on top of cheese. Place 4 to 5 sliced Roasted Peaches on top of leaf lettuce. Place 3 ounces of chicken on top of peaches. Top chicken with 1 slice of toasted bread. Place 2 toothpicks in sandwich. Cut in half diagonally.