This recipe is brought to us by renowned chef Lionel Poilane, whom Salvador Dali referred to as "the greatest Frenchman alive."
Heat oven to 450 degrees. Place chicken in a small roasting pan. Rub with olive oil, and season with salt and pepper. Bake until a meat thermometer inserted into the thickest part of the breast reads 180 degrees, about 25 minutes. Remove from oven, and cool slightly. Remove chicken from bones, and discard bones. Finely chop chicken (there should be about 2 cups).
In a medium bowl, combine chicken, mayonnaise, capers, and lemon juice. Stir to combine. Season with salt and pepper.
Toast four slices bread. Spread a thin layer of chicken salad over one slice untoasted bread. Top with a slice of toasted bread. Spread a second thin layer of chicken salad over toasted bread. Top with a slice of untoasted bread. Repeat with remaining bread and chicken salad.