Once it has cooled to room temperature, transfer any leftover soup to an airtight container. Pop it into the refrigerator where it'll stay fresh and flavorful for up to 3-4 days. When it's time to reheat your vegan Greek lemon soup, there are a couple of methods you can try. The gentlest way is to warm it on the stovetop over low to medium heat, stirring occasionally to ensure even heating. If you're in a hurry, you can use the microwave—just be sure to use a microwave-safe bowl and reheat in short intervals, stirring between each one to avoid uneven hot spots. Whichever method you choose, remember not to bring the avgolemono to a boil, as this can alter the soup's texture and may lead to separation. Once it's nice and warm, grab a spoon and savor the deliciousness all over again!