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Should You Pack Your Herbs?

When measuring fresh basil for pesto, should the leaves be packed?

We had 26 staff members measure out 1 cup of basil in a dry measuring cup and then weighed the leaves. Samples were all over the place—those measuring gingerly ended up with 10 grams of basil; those who aggressively packed in the basil ended up with 29 grams. The average was 18.7 grams.

Based on these weights, we made three batches of our Classic Pesto, which calls for 2 cups of fresh basil leaves (and doesn’t specify packed or unpacked). Tasters liked all three samples. The pesto with more basil tasted, unsurprisingly, more like basil, while the samples with less basil tasted more of garlic, Parmesan cheese, or olive oil. But when pressed to pick a favorite, most tasters agreed: The pesto made with the average amount of basil (18.7 grams) tasted the most balanced and, as one taster put it, “how pesto should taste.”

We went back to the measuring cup with 18.7 grams of basil. We found that laying the leaves in the cup and pressing down just slightly, ensuring that there were no large air pockets, filled the cup just to its brim.

THE BOTTOM LINE: For the best results, measure basil by laying the leaves in the cup and pressing down slightly to remove any large air pockets. Do not pack the leaves down firmly into the cup. Use the same technique for all herbs.

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