The secret of Nopalito’s chicken tostada.

Makes 8 tostadas; serves 4

From Gonzalo Guzman of Nopalito. 8 (6-inch) corn tortillas Rice bran or canola oil, for frying For the tinga 2 bone-in chicken breasts (about 1

pound) 1 small white onion, halved 5 cloves garlic, peeled 3 tablespoons kosher salt + more

to taste 1 large (or 2 small) dried chipotle

chiles 1 (15-ounce) can diced tomatoes 2 teaspoons kosher salt 3 tablespoons chopped fresh

epazote or cilantro For the kefir cream

1⁄2 cup kefir 1 tablespoon fresh lime juice Kosher salt, to taste

For the beans 2 tablespoons finely minced white

onion 2 cups cooked pinquito or pinto

beans (see Note)

1. Fry the tortillas.

In a medium frying pan, heat ½-inch depth of rice bran or canola oil. Line a plate with paper towels. When the oil is hot but not smoking, fry the tortillas one at a time, flipping occasionally in the oil, until golden brown and crisp on both sides. Transfer to the paper towel-lined plate to drain. Set aside.

Nopalito makes its masa daily and uses it for the tortillas. If you want to make tortillas at home, you can purchase prepared masa from La Palma Mexicatessen, which also sells fresh corn tortillas. Fresh corn tortillas can also be purchased directly from the take-out window of the Broderick Street location of Nopalito when the restaurant is open.

2. Make the tinga.

Put the chicken in a large saucepan. Roughly chop one half of the onion, and thinly slice the other half; set aside. Add the chopped onion, 3 cloves of garlic and salt to the chicken. Add cold water to cover, bring to a boil over high heat, then reduce the heat, cover and simmer 30 minutes, until the chicken is cooked through.

Remove the chicken from the water and, when cool enough to handle, remove the skin and bones and shred the chicken. You should have about 3 cups of shredded chicken. Set aside.

Leftover chicken (or chicken pulled from a storebought rotisserie bird) can be used in this recipe.

3. Prepare the chiles.

While the chicken cooks, place the dried chipotle chiles in a small saucepan and add water to cover. Bring to a boil, remove from the heat and let the chiles soak in the water until soft, 20-30 minutes. Remove the stems and mince the chilies.

Guzman uses dried chipotle chiles (smoked, dried jalapeño chiles) in this recipe. You might be tempted to substitute canned chipotles in adobo sauce, but don’t. Says Guzman, “The adobo sauce has a lot of other ingredients in it that would change the character of the stew.”

4.Prepare the tinga.

Rinse the saucepan you used to cook the chicken and place over medium-high heat. Add 2 tablespoons oil (the same oil you used to fry the tortillas is fine) and the thinly sliced onion. Cook, stirring occasionally, about 5 minutes, until slightly softened. Mince the remaining 2 cloves of garlic and add to the onions. Cook, stirring, 1 minute more, then stir in half the minced chipotle chile. You can add more later, to taste.

Add the tomatoes and their juice and the salt. Simmer vigorously about 10 minutes, until the liquid had reduced slightly. Stir in the shredded chicken and epazote. Season to taste with additional salt and/or the remaining minced chile. The tinga should be slightly saucy but not overly wet; if it looks thin, simmer it a bit longer to reduce the liquid. Keep warm over low heat.

Epazote is a resinous green herb used frequently in Mexican cooking; it can be purchased at Mexican grocery stores. Do not substitute dried epazote, which is usually dusty and flavorless; omit it if you cannot find fresh, or substitute chopped fresh cilantro.

6. Make the kefir cream.

In a small bowl, stir together the kefir cream and lime juice. Season to taste with kosher salt.

“I couldn’t find a sour cream or Mexican-style crema that wasn’t loaded with preservatives or stabilizers,” explains Guzman, “so we started using kefir instead.” Plain kefir is widely available.

7. Refry the beans.

In a medium frying pan, heat 4 tablespoons of rice bran or canola oil (the same oil you used to fry the tortillas is fine) over high heat. When the oil is hot, add the minced white onion and cook, stirring, until deep golden brown, 2-4 minutes. Add the beans and sear quickly, agitating them in the pan, until the skins are wrinkled, about 2 minutes.

Remove the pan from the heat and, with a potato masher, coarsely mash the beans. Add a few tablespoons or more of water (or, if you’ve cooked your own beans, some of the bean cooking liquid) and continue mashing until the mixture is creamy and the oil, beans and water are homogenous.

“I know it looks like you’re cooking the beans in a lot of oil,” says Guzman. But it’s refrying — that’s what you do.” He also emphasizes that the beans should be a deep golden brown, and recommends stirring constantly so they darken without burning.

8. Assemble the tostadas.

Smear each tortilla with some of the refried beans. Top with some of the chicken tinga and a spoonful of the kefir cream. Serve immediately.

Note: At Nopalito, the refried beans are made from pinquito beans from Rancho Gordo (www.ranchogordo.com). Instead of cooking them on the stove top, he braises them in the oven. If you want to try it, here’s his method. Rinse the beans and put them in a heavy-bottomed pot with an ovenproof tight-fitting lid. Add 2 cups of water for every cup of beans (Guzman also adds a dried guajillo chile to the pot for each pound of beans). Transfer the covered pot to a 350 degree oven and cook, stirring occasionally, until the beans are tender, about 21⁄2 hours, adding more water as necessary to keep the beans barely covered. When the beans are tender, season to taste with kosher salt.