For substitution, yellow squash can be used instead of zucchini. If you lack ice, rinsing with very cold water can also help stop the cooking process, though ice water is best. Make ahead by freezing in smaller portioned bags for easy grab-and-use convenience. Store zucchini flat in the freezer to prevent clumping. Common troubleshooting: If zucchini turns mushy after freezing, ensure you’re not over-blanching and dry them thoroughly before freezing. For best texture, use in cooked dishes rather than raw applications after thawing.