Enrique Olvera relents only after everyone insists he take over the music at The Washington Post’s Food Lab, where he’s preparing salsas and pressing tortillas from fresh masa. The chef behind celebrated Mexican restaurants in Mexico City (Pujol) and New York City (Cosme) — both claim spots on the World’s 50 Best Restaurants list — wants to hear Toña La Negra, and the late vocalist’s smoky contralto soon fills the room, as sensuous as the food Olvera puts on a plate.

Olvera is making the rounds to promote his second English-language cookbook, “Tu Casa Mi Casa: Mexican Recipes for the Home Cook.” We had originally asked him to prepare the Pistachio Green Mole from the cookbook, but he begged off. He has too much respect for Mexico’s mole tradition to try to dash one off quickly. Mole requires time. Mole requires devotion. Mole requires a metate, a grinding stone, to properly blend the ingredients, the chef insists.

The term “mole” is derived from the Nahuatl word, “molli,” often translated as “salsa,” “sauce” or even “mixture” (presumably because the act of making sauce requires a mixing of ingredients). To Olvera, the mixing process is almost sacred. He would never personally use a blender to combine ingredients for a mole (though, in his recipes, he cuts readers some slack and recommends they use one). The blender changes the texture and, in a sense, the flavor of mole, he says. It’s like his grandmother once told him about salsas: When prepared in a blender, they “taste like electricity.”

I sat down with Olvera to talk moles, a small word that covers a large number of preparations, many more than the chocolate-forward mole poblano known in the United States. Only about 5 percent of moles, Olvera says, incorporate chocolate. The “backbone” of most moles, he adds, is a combination of tomatoes, onions, garlic, dried chiles and “some kind of aromatics.” (This interview was edited for length and clarity.)

Translation aside, how do you define mole?

I would say it’s a technique more than a dish. The technique varies from town to town and from region to region, from season to season and from family to family. You cannot say it’s a sauce, because sauces tend to be almost thinner. It has a thicker consistency. It’s normally served for special occasions. You wouldn’t make mole just because it’s Tuesday night and you’re cooking at home. It’s a celebratory dish, because it is so high in labor.

Are there celebrations where mole is mandatory?

Definitely with weddings. Most Mexicans, when they marry, there is mole. Maybe in Mexico City, everything has changed a little bit with modernity. But in all small communities, you’ll see a mole being made.

One requirement for mole, I’ve read, is that every ingredient is manipulated in some way before it’s incorporated into the dish. Do you think that’s true?

I would say none go in raw. For example, onions, garlic and tomatoes, you would char on a comal or roast in an oven. Then peppers, you can either fry in oil or you can char. You can char them until they’re ash. The level of char-ness will give you the color of the mole. It’s almost the same recipe for both red mole and black mole. The only thing that changes is the level of char-ness of the ingredients and a little bit of the spice combination.

I’ve seen moles where cooks take the ingredients, including tortillas, and light them on fire on a comal, so that they turn into ash. I can’t imagine putting that technique into a cookbook. I think half the kitchens in America would go up in flames.

[Laughs] That’s probably a fire hazard, indeed. Mexican cooking responds to a different set of techniques. If you’re used to cooking French or Italian or some kind of European cuisine, everything in Mexican food is almost contradictory to that. If not contradictory, at least radically different. Classical French is a cuisine that has evolved through novelty. Mexican food was always in the markets, in the houses, in very casual restaurants. I think that is the difference. It has stayed closed to the people, and it hasn’t changed. So burning seeds and burning tortillas, it’s something you probably would do at home, never in a restaurant setting.

I think there’s a sense that the “seven moles of Oaxaca” are exactly that: seven and nothing more. But that’s not how we should think about the seven moles, right? They’re just broader umbrella categories, such as green, yellow and black moles.

With just one style of mole, there can be so many variations. Kind of like when you’re talking about corn. If you say “yellow” corn, there are so many yellow corns with so many different shapes. It’s the same in Oaxaca with moles. Obviously, this is something that helps us understand the world of mole, but each town will have a different recipe. For example, we could talk about “coloradito,” which is one of the seven moles. That mole is thickened with masa. Normally, you would eat it with vegetables and a very small amount of chicken or pork. It almost has a soup consistency. You would never eat a soup of black mole. Because black mole is a celebratory dish, it gets eaten with chicken. So you would kill your animal, which you wouldn’t do normally because it gives you eggs. That tells you the mole is celebratory, because it has chicken.

I saw in one recipe where a cook was using Ritz crackers to thicken her mole, and it made me wonder where processed foods fit into the dish.

I wouldn’t use processed foods, but I’m not going to pass judgment on it either, because cuisine is always moving. I’m sure whoever thought of mole poblano was probably criticized because it was not traditional. Normal mole poblano has nothing to do with pre-Hispanic moles. Pre-Hispanic moles were not as complex, and they probably didn’t have chocolate — at least not like that.

Since mole can take so long to prepare, do restaurants take shortcuts?

The problem is that most restaurants don’t have a stone mill. It’s kind of like the same thing about the electricity and salsas. If you’re doing a mole in a blender, you’re probably not going to have a good texture. Good moles are usually done either in a stone mill or in a metate. If you go to smaller towns, you’ll see like 10 to 15 women on a metate, grinding the mole by hand. The flavor is entirely different, and the texture is entirely different as well.

At Pujol, you have a mole, called Mole Madre, that has been aged for more than 1,000 days. What’s the process for making it?

We make mole, for example, on a Tuesday. We make like 50 liters of mole. Then in the morning, we’ll heat up the mole, and that’s the mole we serve on the first day. Then we’ll reheat it the next day and we’ll reheat it the day after that. Then we start running out of mole. So we make a new batch and add the old mole to the new mole, and start reheating. That’s why we never run out of it.

So the new mole always has some of the old mole. Do you think there’s still some of the very first mole in the new mole?

[Laughs.] A very minute amount.

More Enrique Olvera recipes:
Raw Salsa Verde With Cucumber and Mint

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