We grew basil like crazy last season, harvested it and froze it whole in freezer bags as it came due in order to keep up with it instead of trying to make it all into pesto right away. It was a good strategy because we accumulated enough to get us through April. I think the previous year I ran out by Christmas. If you do it this way, the primary benefit is you can eke out more production from your plants by constantly harvesting. Otherwise they go to seed before you know it and they are done.
The routine of making basil pesto this way with frozen leaves every two weeks or so right through the fall, winter and spring had more than this extra production benefit from the plants, however.
For one thing, I was constantly using the freshest olive oil, instead of freezing the oil in the prepared product for long periods.
Two, I didn't have to buy a bunch of little containers which took up a lot of space and were difficult to keep organized in the bowels of the freezer. I simply relied on a smaller number of containers and reused them throughout the season, conveniently stored in a single freezer bag. The basil leaves once frozen in freezer bags store easily by themselves in those bags grouped altogether in a single, larger plastic bag, like a grocery bag.
Three, I had less waste and clean up hassle on a regular basis because at the end of making the pesto, say each fortnight, the hard to clean up leftovers in the blender simply were blended with tomato sauce for my once or twice a week fish pie recipe. If you don't make that you could do the same thing for fresh tomato-basil soup. So I tried to time my pesto-making with fish pie night to speed things along, minimize waste and wasted motion.
And four, extra virgin olive oil doesn't like to be manipulated too much. If it gets hot it breaks down quickly. By using frozen pesto leaves, the whole mixture remains cold in the blender. And when it is done blending it looks almost like a gelato and pours out more neatly cold, minimizing spills.
So here's how you do it.
Add your nuts, salt and pepper, chopped garlic and grated cheese to the bottom of the blender. Then add your crushed basil leaves on top of all that. I simply take the freezer bag full of basil leaves and slam it on the counter a few times to make them easy to pour into a Pyrex measure (and more numerous, hah!). Finally, I add all the olive oil on top of the leaves, letting the measuring cup drain out fully on top of them while I clean up after myself. Then you blend until thoroughly emulsified, perhaps a minute or two. And that's it.
Pesto, presto!
