This approach makes pesto that's less grassy and intense than raw basil versions, with rounded, balanced flavor.
It's good to use a mellow, mild olive oil here so it doesn't detract from the fresh herbs. If you don't care for the hot taste of raw garlic, you can take the edge off the cloves by blanching them along with the basil. We use sunflower seed kernels here because they are far less expensive than the pine nuts traditionally used, and their flavor is similarly rich and sweet. If you have pine nuts already on hand, feel free to use them instead.
1. Start by blanching.
Giving fresh basil a quick dip in boiling water followed by an ice bath results in brilliant, emerald-green pesto that keeps its color far longer than basil that goes straight into the blender. Place the basil in a heatproof strainer then into boiling water to make the leaves easy to scoop out quickly.
2. Shock and dry.
Immediately after pulling the leaves from the pot—as soon as they become bright green—dunk them into an ice bath for 10 seconds to stop the cooking. Drain well, spread the leaves onto a clean, dry dish towel, and gently blot dry with another towel. A little water content will remain—and that's actually good for the pesto, as you'll see.
3. Blend to a puree.
Combine basil, toasted seeds or nuts, garlic, salt, and olive oil in a food processor, and blend until smooth. The small amount of residual water on the leaves from blanching will emulsify with the oil. Finally, add the cheese—it further emusifies with the water and oil to make the pesto wonderfully creamy.
4. Bask in the green glow.
The end result is noticeably bright than raw pesto, and it's made to stay that way. Blanched pesto won't brown if you add a squeeze of lemon or toss it with hot pasta. What's more, its flavor is rounder and more mellow than conventional basil pesto, which can taste a little "hot," between peppery uncooked basil and the pungent raw garlic.