Serve the frozen squares immediately, returning any leftovers to the freezer right away so they stay firm and creamy for next time.
For a slightly tangier version, swap half of the sour cream for plain Greek yogurt; it keeps the creaminess while adding a little extra bite. If you prefer a softer, more scoopable texture, reduce the freezing time to about 2–3 hours and serve it semi-frozen like a soft-serve dessert. You can also toast the walnuts in a dry skillet for a few minutes before chopping to deepen their flavor and add extra crunch. If you like more texture, reserve a few extra peach slices to fan across the top before freezing for a more defined fruit layer. For a lighter sweetness, cut the sugar back to 1/3 cup, especially if your peaches are packed in syrup. To make this easier for weeknights, mix and assemble the salad on a Sunday, freeze it in the same clear glass pie plate, and slice off squares as needed for a quick, ready-to-go dessert all week long.
