A sauce from the Liguria region of northwestern Italy, pesto is traditionally made with garlic, basil, Parmesan cheese, olive oil and pine nuts.

Chefs have tweaked the recipe endlessly and there many possible variations. Don’t like expensive pine nuts? Try almonds, cashews, walnuts, pistachios, or hazelnuts in the place of pine nuts.

Want more than just basil? Add parsley, romaine, spinach, or kale to the basil leaves.

When garlic scapes are available, they provide both garlic flavor and green color. They can take the place of some of the basil and garlic.

For more zip, toss in red pepper flakes, to taste. Pecorino, Asiago or Gruyere are substitutes for, or additions to, Parmesan cheese.

The following is a basic recipe. Adjust to your taste.

1/3 cup pine nuts

2 cups packed fresh basil leaves

2-3 garlic cloves, peeled and lightly chopped

½ cup grated Parmesan cheese

¼ teaspoon salt

½ cup extra virgin olive oil

Toast the nuts in a dry pan until lightly browned and fragrant; let cool. Process the nuts in a food processor until ground. Add fresh basil leaves, chopped garlic cloves, grated Parmesan cheese and salt to the processor, and pulse to combine. Slowly pour in the olive oil while the food processor is running, to incorporate all the ingredients. Yields about ¾ cup pesto.

NOTE: ½ cup pesto, more or less, can be used for a pound of pasta.