Lay basil leaves overlapping in an 8 inch line on plastic wrap. Continue laying leaves over the original line moving the next line slightly higher so that your line is getting wider. When you have the line approximately 4 inches wide or more, use the plastic wrap to help gather the contents from bottom to top into a cigar shape. After gathering and holding the contents in place, wrap the plastic wrap around tightening the roll even more, then twist ends closed. Freeze. When ready to use, unroll one end and snip off frozen into your recipe.
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Here is a new way to preserve basil from the garden for winter use without drying it. You can not freeze basil by itself because it will turn black in the freezer.