Freezing basil is a practical way to make this seasonal herb available year round or simply to store excess to avoid spoiling. Generally, the best ways to freeze basil is to chop the leaves and then add either oil or water. The mixture of basil and liquid can then be portioned into a variety of different containers and set in the freezer to harden. Frozen basil can be added to a multitude of recipes — especially soups and sauces — to impart a fresh herb flavor even in the off-season.
Basil plants that are grown outdoors need warm, sunny climates to thrive. People who live in areas that do not experience ideal growing conditions year-round might still desire the addition of fresh herbs to their meals during colder, darker months. Freezing basil is also useful for people living in year-round basil-growing weather if their plants are so prolific that the basil yield surpasses how quickly the fresh leaves can be consumed.
There are a few basic guidelines to follow to ensure success when freezing basil, but the process also allows for enough variation to account for personal preference and facilitate different methods of use. The first step is to harvest the basil leaves and carefully wash and dry them. After the leaves have been cleaned it is time to chop them, either with a knife or in a food processor fitted with a metal blade. It is important that the chosen blade be sharp enough to slice neatly through the leaves; a dull blade might bruise the delicate leaves and cause browning.
The texture of the chop can range from a rough, uneven chop to a very fine mince, depending on personal preference or the nature of the dish the basil will eventually be used in. After the leaves are chopped, the basil can either be mixed with water or oil to help them fuse together and prevent browning. If a food processor is used to chop the leaves, just enough oil or water to coat the leaves can be streamed into the mix with short pulses. Basil that was chopped by hand can be placed in a bowl or container and the liquid stirred in with a spoon.
Once the mixture has been made, the next step in freezing basil is choosing a container. Technically, any freezer-safe container that can be sealed can be used, but there are some that do the job better than others. Unless the ultimate goal is to thaw a large amount of basil all at once, it is a good idea to freeze the basil in small containers so servings can be thawed as needed. Ice cube trays are a great example of a convenient vessel for freezing basil: the trays are easy to fit into the freezer, and the resulting basil cubes will be consistent in size and easy to measure.