When you first slice a raw spaghetti squash open, it might look very similar to any other squash. After you cook it, however, you will understand where it got its name. When you pull a spaghetti squash's baked flesh out of the skin, it will separate into strands that look very much like true spaghetti. If you cannot finish all of the squash after cooking it, freeze the leftovers. With proper care, you can keep frozen spaghetti squash for up to eight months.
Remove the cooked spaghetti squash's flesh from the shell if you have not done so already. Comb through the flesh from top to bottom with a fork, then scoop the flesh out of the shell. Combing the fork through the squash will help separate the squash's strands, leaving the finished product looking more like real spaghetti.
Transfer the spaghetti squash strands into freezer-safe containers. Ideally, you should use freezer bags, as you can remove more air from these, but you can use rigid freezer containers instead if necessary. Remove as much air as possible if you are using bags, then seal the bags or containers tightly.
Put the packaged cooked spaghetti squash into your freezer. You can freeze it for six to eight months before its quality declines.
Label the bags with the contents and date you froze them if you think you may not remember. This will help you determine whether they are still good when you are ready to use them.
If your spaghetti squash is still hot, pack it as described but allow it to cool to near room temperature before you put it into the freezer.