It’s been a warm autumn so far, but the days of the basil plant are numbered.
Basil is always the first plant in the garden to die of cold—it doesn’t have to be an actual frost, just a cool night in the 30s, and every basil plant will turn black, withered and useless. So when I run out of home-grown tomatoes to enjoy with the basil, I pull my remaining basil plants. I dry some of the leaves, crumble them and keep them in a tin in my spice cabinet. Sometimes I put a teaspoonful of chopped fresh leaves in each chamber of an ice cube tray, fill it with water and store the ice cubes in zipper bags in the freezer. The basil turns black (just as it would out in the cold in the garden), but it still tastes good, and the ice cubes can be added as needed to season soups and stews. I make the rest of the harvest into pesto base.
I’m not sure where I got this pesto recipe. It’s probably from a newer edition of The Joy of Cooking. I found it on a slip of paper in my own handwriting stuck into my older edition of Joy. To the work bowl of a food processor, add two cups of fresh basil leaves, 2 peeled cloves of garlic, 1/3 cup pine nuts, and ½ cup of grated Parmesan cheese. Pulse until it forms a paste. Then, with the motor running, slowly pour ½ cup of good olive oil through the feed tube.
When I’m making basil pesto in bulk at the end of the growing season, I leave out the nuts and cheese and freeze the paste in a zipper bag. I thaw the pesto base on the day of use, add the nuts and cheese, and buzz it all up together one more time in the food processor.
My food processor will make one triple batch of pesto base at a time. I’ve also made this recipe using a blender. The owner of a gourmet kitchen store (the same man who gave me the tip about freezing basil in ice cube trays) told me that pesto isn’t right unless it’s pounded in a mortar by hand (he said this as I was buying a mortar and pestle from him). If your taste is refined enough that you insist on manually ground pesto, feel free to adapt the recipe for mortar and pestle. But with the food processor, I can make a year’s supply of pesto base within an hour of pulling the plants, and I can’t tell the difference.
