Enjoy this salad with your favorite crisp apples, and feel free to experiment with different varieties along with your classic favorites. Substitute any seedless grapes you prefer for the red grapes, just be sure to slice them in half. You can prepare this salad up to 24 hours in advance and store it in an airtight container in the refrigerator until serving. For a twist, swap the pecans with chopped walnuts, pistachios, macadamia nuts, pine nuts, or sunflower seeds. Store any leftovers in an airtight container in the refrigerator for up to three days. Note that this salad does not freeze well.