The best way to store the cooked green beans is to wait until they cool down to room temperature, then transfer to an airtight container and store in the fridge for up to 2-3 days. To freeze them, if cooked in a stew, put them in a suitable for freezer and container and freeze for up to 3 months. Another option is to blanch the fresh green beans, put them in a bag when they come at room temperature, then freeze them for up to 4-5 months. This way you can have green beans for stews and casseroles in the winter.