In a medium bowl, combine the chicken and buttermilk. In a small bowl, stir together the mayonnaise and pickled jalapenos.
In a shallow bowl, combine the pecans and bread crumbs. Working with one piece at a time, remove the chicken cutlets from the buttermilk, letting the excess drip off, and coat with the pecan mixture.
In a large skillet, heat the olive oil over medium heat. Add the cutlets and cook, turning once, until golden-brown, about 2 minutes on each side. Drain on paper towels.
Spread the jalapeno mayonnaise on the cut sides of each kaiser roll. Assemble sandwiches with the chicken, peach and lettuce.