Chimichurri

• 1 large bunchflat-leaf parsley · about 2 packed cups of leaves and thin stems, washed and dried completely
• 2 tbspfresh oregano leaves · or 2 tsp dried Mexican oregano, crumbled between your palms
• 6 clovesgarlic · minced very fine by hand, not pressed
• 1 wholered chile · a fresno or a red jalapeno, seeded and minced, or 1 tsp red pepper flakes
• 1/2 cupred wine vinegar · a decent one, this is half the flavour of the sauce
• 1 1/4 tspkosher salt · added to the vinegar, not to the oil
• 1 smallshallot · minced, optional, and not traditional in Argentina
• 3/4 cupmild olive oil · not a peppery extra-virgin, it fights the herbs
• 1/2 tspblack pepper · coarsely cracked
• 1 pinchground cumin · optional, about 1/8 tsp, common in the Buenos Aires versions
• 2 tbspwater · cold, to loosen the sauce at the end if it has tightened

Method

1. 1

   Put the food processor away, and here is the actual reason

   Blades bruise. A spinning blade ruptures the cell walls of parsley on a scale that hand-chopping never does, which releases chlorophyll and the bitter compounds that sit with it, and it emulsifies the oil into the water in the leaves. You get a thick, opaque, faintly bitter green paste that pools instead of running. Hand-chopped chimichurri stays loose and translucent, the oil sits separately and clings to whatever you spoon it over, and it tastes of parsley rather than of green. Fifteen minutes with a sharp knife is the whole difference.

2. 2

   Dry the herbs like you mean it

   Wash the parsley, spin it, then lay it on a towel for ten minutes while you do everything else. Water left on the leaves does two things, both bad: it dilutes the vinegar so the sauce tastes flat, and it sits under the oil layer in the jar where it shortens the fridge life from two weeks to about four days. If you are in a hurry, spin twice and press the bundle between two towels. Damp herbs are the most common reason a homemade batch goes cloudy overnight.

3. 3

   Use the thin stems, discard the thick ones

   The thin stems at the top of a parsley bunch carry more flavour per gram than the leaves and chop down to nothing. The thick lower stems are fibrous and stay stringy no matter how fine your knife work is. Grab the bunch, cut across it about an inch below where the leaves start, and throw the bottom half in the stock bag. You are aiming for roughly two packed cups of usable material, which is one large supermarket bunch or a bit more.

4. 4

   Chop to the size of a match head, and stop there

   Gather the parsley into a tight pile, rock a large sharp knife through it, regather, repeat. Three or four passes. You want visible flecks about the size of a match head, not a mince and not a mush. If the board is going wet and dark green under the pile, you are past the point and the knife is dull. A dull knife tears rather than cuts and gives you the same bruising problem as the processor, in slow motion. Sharpen it first if you have any doubt.

5. 5

   Mince the garlic by hand, never through a press

   A garlic press ruptures every cell at once, which maximises allicin production and gives you a hot, sulphurous note that dominates the sauce for the first day and turns acrid by the third. Hand-minced garlic releases less of it and mellows properly in the vinegar. Six cloves sounds aggressive and is correct for this volume, because the acid and the rest period take most of the edge off. If you are nervous, use four and add more after the rest.

6. 6

   Salt and vinegar first, oil last, and that order is not arbitrary

   Combine the vinegar, salt, garlic, chile, shallot and oregano in the bowl and let them sit for five minutes before anything else happens. Salt dissolves in the vinegar, the garlic and chile start to soften in the acid, and the dried oregano rehydrates. Add the oil first and you coat every particle in fat, the salt never dissolves properly, and you end up with a sauce that tastes simultaneously under-seasoned and gritty. Five minutes of patience here is worth more than any ingredient upgrade.

7. 7

   Mild oil, not your best peppery extra-virgin

   A green, grassy, high-polyphenol extra-virgin olive oil is a wonderful thing on bread and the wrong choice here, because its own pepper and bitterness stack on top of the raw garlic and the sauce ends up harsh. Use a mild or light-tasting olive oil, or cut a good extra-virgin half and half with a neutral oil. In Argentina this is often made with plain sunflower oil for exactly this reason. Stir the oil in with a spoon rather than whisking, because you are combining, not emulsifying.

8. 8

   Thirty minutes at room temperature, and no longer than a few hours

   Cover the bowl and leave it on the counter for thirty minutes. The garlic rounds out, the salt distributes, the oregano softens, and the parsley gives up a little colour into the oil. Taste before and after and the difference is obvious. Past about four hours at room temperature the parsley starts to dull and the vinegar dominates, so if you are making it in the morning for dinner, refrigerate after the first thirty minutes and pull it out an hour before you eat.

9. 9

   The ratio, and what to change when you taste it

   This is roughly one part vinegar to one and a half parts oil, which is sharper than a salad dressing and deliberately so, because the sauce is meant to cut through fat. If it tastes harsh on a spoon it is probably correct on a steak. If it tastes flat, it needs salt rather than more vinegar, nine times out of ten. If it tastes dusty, the dried oregano was old. If it tightens up in the fridge, loosen it with the two tablespoons of cold water rather than more oil.

10. 10

    Chimichurri rojo, if you want the other one

    The red version is the same sauce with a tablespoon of sweet paprika or pimenton and a small grated ripe tomato stirred in at the end, and the parsley cut back slightly to make room. It is heavier, sweeter and better on chicken and roasted vegetables than on beef. Make it the same way and in the same order. Do not add the tomato until after the rest period, because it waters down the acid the garlic is supposed to be softening in.

11. 11

    What it goes on, beyond the obvious steak

    Grilled or roasted anything with a browned surface, because the acid needs something rich to cut. Skirt and flank steak first, then lamb, then chicken thighs. Spooned over roasted potatoes or charred broccoli it turns a side into the reason for dinner. Stirred through white beans with a little of their cooking liquid it is a whole vegan lunch. It is also very good on a fried egg, and it is compliant as written for whole30 and paleo eating.

12. 12

    Storage, and the two-week honest answer

    In a clean jar with the oil covering the solids, refrigerated, this holds two weeks and is at its best between day one and day five. The parsley darkens from bright to olive over that time, which looks worse and tastes fine. Do not freeze it, because the herbs turn to slime on thawing. Never leave it at room temperature overnight: raw garlic in oil is the classic home setting for Clostridium botulinum, and the acid here helps but the fridge is what makes it safe.

13. 13

    Using it as a marinade, and the ninety-minute ceiling

    Chimichurri makes an excellent marinade for skirt, flank and hanger steak, and a poor one if you leave it on too long. At roughly one part vinegar to one and a half parts oil it is acidic enough to start denaturing the surface proteins, and past about ninety minutes the outer few millimetres go pale, chalky and slightly mealy in a way that survives the grill. Thirty to sixty minutes at room temperature is the window. Always split the batch first and keep the table portion in a separate jar, because anything that has touched raw meat cannot come back.

14. 14

    Why it separates in the jar, and why that is correct

    Within an hour of resting, the oil rises and the herbs settle, and the jar looks like two layers. That is the sauce working as intended: chimichurri is a suspension, not an emulsion, and there is no egg, mustard or starch in it to hold the two phases together. Stir it back with a spoon before every use and it comes straight back. If yours does not separate at all, something is emulsifying it, which usually means it went near a blender, and the texture will confirm it.