Making Ligurian Pesto
A specialty of Liguria, Italy, pesto is traditionally prepared with a mortar and pestle for maximum taste and ideal texture. The grinding action of the pestle produces a smooth texture and brings out the full flavor of the ingredients.
Put basil, pine nuts, garlic and salt in the mortar. Using a rotating motion with the pestle, grind the ingredients against the sides to form a paste. Then add Parmigiano-Reggiano cheese and grind in a circular motion until blended.
Drizzle in a thin stream of olive oil while stirring quickly with a wooden spoon. Taste the pesto and adjust the seasonings with salt.
Williams-Sonoma Test Kitchen