pestos

Pesto is a sauce that originated in Genoa, in the Liguria region of Italy. Traditionally, it is made by crushing fresh basil leaves with pine nuts, garlic, and coarse salt, then blending in olive oil and grated hard cheeses such as Parmigiano-Reggiano and Pecorino Romano. The word pesto comes from pestare, meaning to crush or pound. The term pestos is used for a family of green sauces that share a similar method or ingredients, with regional variations.

Traditional preparation uses a marble mortar and wooden pestle, which slowly grinds the ingredients and emulsifies the oil for a thick, cohesive paste. Modern kitchens often rely on electric blenders or food processors, producing a range of textures from coarse to smooth.

The best-known variant is Pesto Genovese, defined by basil, pine nuts, garlic, olive oil, and two cheeses. Other pestos include pesto alla Siciliana and pesto rosso (red pesto), which incorporate almonds or sun-dried tomatoes and sometimes omit basil. Numerous greens can be used, such as arugula, spinach, or kale, and nuts beyond pine nuts—walnuts or almonds—are common substitutions. Variants may also feature ricotta or other cheeses and vary by region or personal preference.

Uses include tossing with pasta, spreading on bread or crostini, or serving as a sauce for grilled fish or poultry, potatoes, or vegetables. Storage typically involves refrigerating in an airtight container, often with a thin layer of oil on top to prevent oxidation; it can keep for several days and freezes well for longer storage. Pine nut allergies or dietary restrictions may lead to alternative versions.