1/4 teaspoon salt

1/4-1/2 cup extra-virgin olive oil

1. Combine half of the basil with the nuts, cheese, garlic and salt in a blender or food processor. Blend continuously until the ingredients are finely chopped.

2. Scrape down the sides of the bowl and add the rest of the basil. Blend until a uniform paste has formed. Scrape down the sides of the bowl as needed.

3. With the blender running, stream in the olive oil. Less olive oil will make a paste good for spreading on sandwiches and pizzas; more will make a sauce better for pastas and stirring into soup. Scrape down the sides of the bowl and continue blending as needed until the olive oil is emulsified into the basil and the pesto looks uniform.

4. Taste the pesto and add more salt, garlic, nuts or cheese as needed to taste.

Note: Pesto will darken and brown very quickly, but it will still be tasty and fresh for several days. For best appearance, use it right away. If storing, keep it in the smallest container possible and thoroughly press the pesto to eliminate air pockets. Pour a little olive oil over the surface, cover, and refrigerate for up to a week. Pesto can also be frozen for several months.

(Emma Christensen is a writer for TheKitchn.com, a nationally known blog for people who love food and home cooking. Submit any comments or questions to kitchn@apartmenttherapy.com.)