Rub tenderloins with oil, season with lemon pepper and a sprinkle of salt to taste. Rest at cool room temperature and preheat a medium hot grill (375-400°).
Grill tenderloins over medium high coals, turning regularly to brown evenly and cook to 145-150 degrees internal. Remove, cover and rest for at least five minutes. Slice thinly and keep in shape.
Meanwhile saute onions in butter until soft. Add peaches, sugar salt, cinnamon, cloves, bay, lemon and wine, stir well, cover and bring to a boil. Reduce heat and simmer covered until peaches are tender and thick sauce forms. Taste and adjust as desired.
Pour sauce into a large serving plate and top with slices of tenderloin. Sprinkle with julienned basil just before serving.