Last week, when I wrote about my recipe for phat phrik khing, I tried my absolute darnedest to convince you that a good mortar and pestle belongs in the arsenal of any home cook (and Daniel's done the same in his guide to the best mortars and pestles). This tool will actually extract more flavor from herbs and spices than a food processor or blender ever can, producing chili paste that's more aromatic, spoonful for spoonful. (You can read about how to pick the right mortar and pestle for you here.) I'm going to try to convince you once again today with zhug (also spelled "s'chug" or "s'rug"), a Yemenite hot sauce flavored with coriander (cilantro) seeds and leaves, cardamom, cumin, parsley, and plenty of heat from chili peppers.
The sauce is actually quite similar to a South American chimichurri, North African chermoula, Spanish- or Italian-style salsa verde, or even a good pesto. In other words, it's an herb-packed sauce that's pounded or roughly puréed and emulsified with plenty of olive oil.
I love it when you find recipes that so closely resemble each other from all corners of the globe. It means that you can instantly travel from one region to the next, with only minimal changes in ingredients and process.
As with all other pound-fresh-ingredients-until-they-drop recipes, I found that, as promising as a high-powered mechanized solution looks, the real key to the best-tasting zhug is taking the food processor out of the equation and pounding your ingredients with a mortar and pestle.
I start with kosher salt (which mainly acts as an abrasive to improve grinding) and spices: cumin and coriander seed, along with some black pepper and the interior seeds of a couple of cardamom pods. Grinding these is quick work with a mortar and pestle; you need to use a series of firm, circular motions. Next, I add garlic cloves and Thai bird chilies—I prefer their intense heat and fresh flavor to the more bitter, grassy flavor of the jalapeños that many recipes call for. I crush them all into a rough paste, using a pounding and twisting motion. The mortar and pestle does require a bit of elbow grease, but the results are just so much better than what you get out of the food processor.
Once the garlic and spices are broken down, I add my leaves half a handful at a time, working the cilantro and parsley into a rough, pulpy paste. Finally, I drizzle in extra-virgin olive oil, smashing and grinding the entire time so that the olive oil gets emulsified into the sauce, while also picking up flavors from the herbs, chilies, garlic, and spices.
The final sauce is fresh and bright from the herbs, while also having an intensely spicy kick to it. It's the ideal accompaniment for falafel or sabich sandwiches, but it also goes great with a variety of grilled vegetables, fish, meat, and eggs. It should last a few weeks in the fridge (though I've never had a jar linger uneaten for long enough to actually find out).