From America's Test Kitchen
In the Sicilian village of Trapani, there’s a very different kind of pesto—it’s basically pesto crossed with tomato sauce. Almonds replace pine nuts, but the big difference is the appearance of fresh tomatoes—not as the main ingredient, but as a fruity, sweet accent. We wanted a recipe for a clean, bright version of this sauce, not a chunky tomato salsa or thin, watery slush.
For an uncooked sauce, fresh tomatoes were best. Cherry and grape tomatoes proved equal contenders, sharing a similar brightness and juiciness that was far more reliable than that of their larger cousins. We added a scant amount of hot vinegar peppers for zing, then drizzled in olive oil in a slow, steady stream to emulsify the pesto. Parmesan was stirred in for the finishing touch to this light, bright, and texturally satisfying pesto.
Serves 4 to 6
A half teaspoon of red wine vinegar and ¼ teaspoon of red pepper flakes can be substituted for the pepperoncini. If you don’t have a food processor, a blender may be substituted. In step 2, pulse ingredients until roughly chopped, then proceed with the recipe, reducing processing times by half.