I guess you could say that I have been on a “Kenji kick” lately, channeling my secret inner scientist and learning so much about food that I can hardly keep up. If you’ve been following my posts, you know how inspired I am by J. Kenji López-Alt, the chef who pushes all the boundaries of science and food, and today, I present another example of new tricks I’m learning from Kenji.

I have attached the name “street corn” to this recipe, though it is technically missing a few of the signature street corn ingredients (specifically, mayonnaise and chile sprinkles). But the mouthwatering combination of flavors it does have—lime, cilantro, grilled corn and cotija cheese—gives me such an impression of street corn that I couldn’t help myself.



Besides, I felt an obligation to change the name because I couldn’t quite make the recipe (which comes from the pages of NY Times Cooking) as directed by its author, and that’s because I don’t have the proper tools of a Mexican cocina. Nope, this gringa relies mostly on her countertop electrics for heavy chopping, dicing, mincing and pureeing, and that works fine most of the time. But when it comes to making salsa or guacamole, the better and more authentic method would involve a molcajete, a huge, primitive looking mortar and pestle carved from a chunk of volcanic rock.
The rough interior of a molcajete (pronounced mowl-kuh-HAY-tay) makes the flavors more intense, because as you grind solid ingredients into it, you crush rather than chop, and that releases the essence of seed spices, herbs and onions in a way that modern appliances simply can’t compete. For this recipe, even though I recently spent several hundred dollars on a made-in-France food processor that basically requires a college course to use, I set out instead to find a molcajete, a culinary tool that you have probably seen in Mexican restaurants.
Originally, my plan was to share this scrumptious guacamole recipe in observance of Hispanic Heritage Month, but my research about molcajetes led me to realize that the tool really is primitive, and it is considered “pre-Hispanic” because it was created and used by the Aztecs, long before Spain began to influence the cultures that we recognize today as Hispanic—including Mexico, where most molcajetes are still made to ancient standards.

My first stop for one of these nifty devices was Amazon, but after scrolling through three pages of “authentic” molcajetes, I wasn’t convinced that they weren’t made in China, and possibly of concrete. Next stop, Williams-Sonoma, because who knows more about authentic Mexican cooking, right? OK, maybe not, though they did have some impressive-looking molcajetes, and (not surprisingly) at really impressive prices.
Finally, I wised up and headed across town to the Mexican supermarket. Les and I love visiting this interesting store, where we find all the spices, dried peppers and other Mexican ingredients we could ever want. They have the largest bin of fresh jalapenos I have ever seen (perfect for Les’s Atomic Buffalo Turds recipe), as well as a few ingredients I can’t pronounce and wouldn’t begin to know how to use (yet). English is not the first language for the workers in this market, nor for most of its customers, and I’m good with that because every visit feels like an adventure.

This is the same store where I found my cast iron press for making handmade corn tortillas, and I knew we would find a traditional molcajete as well—and there it was, conveniently nestled among all sorts other gadgets, right next to the carousel rack of shampoo and rubbing alcohol, of course. As I said, it is an interesting store (remind me to tell you sometime where to find the mayonnaise)!
What I had not realized at the time of my molcajete purchase was the curing, or “seasoning,” that is required. The pores are huge in the volcanic rock, and a great deal of dust and grit is encased in there. First, you must scrub the inside and outside with hot water (no soap) and a stiff-bristled brush to release the surface grit and grime, and tip it sideways to air dry. Then you grind raw, whole rice into the thing, which draws out additional gray, powdery grit.
You rinse and repeat as many times as it takes, until the rice comes out clean. At that point, you’re ready—unless you follow some experts’ instructions to also season the food-touching surfaces with salt and garlic. OK, all of that sounded time consuming, but easy enough!
Or, maybe not.




A mere 20 minutes into this process, I had to give up because I already had a blister from gripping the rough surface of the pestle so tightly. Les took a crack at it, too, and we soon realized this was not going to happen in time for us to make Kenji’s gorgeous guacamole, and that’s where the chef’s scientific expertise came to the rescue. As with most of his recipes, Kenji offered a workaround for crushing the ingredients with coarse salt, and it was so simple, we could do it with nothing more than a bowl, a cutting board and a good knife. Here goes!




Salting the white onions, jalapeno and cilantro for 15 minutes breaks down the cell walls and makes it easier to extract the flavors than if you started chopping it straightaway. Next, you mince that mixture finely, and then lay the blade of your knife nearly flat against the cutting board, dragging the mixture to a paste-like consistency. Transfer it to a bowl and carry on with the recipe.




We grilled our corn ahead of time and stripped off the kernels, but I imagine in a pinch you could even use (thawed) frozen fire-roasted corn, like the kind we frequently buy at Trader Joe’s. Squeeze lime juice over the avocados to preserve their color, and use a box grater to shred the cotija cheese into coarse crumbles. Blend it all together, mashing the avocado with the back of a fork or potato masher, and reserve some of the corn and cotija for topping your beautiful creation.




Friends, this guacamole was so freaking delicious, the two of us devoured the entire bowlful in less than half an hour!

You can make the guac as spicy as you want it to be by adjusting the jalapeno, or simply by leaving in some of the seeds. Choose the most ripe, ready avocados you can find and, if you don’t have a molcajete, take advantage of the workaround that Kenji shared because it really does make a difference. I readily admit that up to this point, Les and I had merely cut up our guacamole ingredients, but we look forward to applying this fabulously simple technique the next time we make the Smoky Chipotle Guacamole that Les has made famous at our house. And, of course, we will continue to grind away at the molcajete—hopefully, it will be properly seasoned in time for Super Bowl!
Mexican Street Corn Guacamole

Even without the proper, authentic tools, I found this Kenji-inspired appetizer very manageable and absolutely delicious! Save yourself some time by grilling an extra ear of corn a day or two ahead, and use avocados that are at peak ripeness!
Ingredients
- 1/4 cup white onion, rough-chopped
- 1 jalapeno, seeded and rough-chopped
- 1 cup loosely packed cilantro leaves and tender stems
- 1/2 tsp. kosher salt or coarse sea salt
- 1 ear grilled corn, cooled
- 2 average size, ripe avocados
- Juice of 1/2 large lime
- 2 oz. cotija cheese, shredded on large holes of box grater
- Additional salt, pepper and lime to taste
- Tortilla chips for serving
Directions
- Combine onions, jalapeno and cilantro in a medium bowl and toss it with the kosher salt. Allow it to rest 15 minutes, to draw out moisture. Finely chop these ingredients together, then lay a chef’s knife nearly flat and drag them across the cutting board to create a mixture similar to paste. Some bits will remain, and that’s OK. Transfer the mixture to a bowl that’s large enough for mixing your guacamole. During the rest time, prep the corn and cotija.
- Trim the fat end of the ear of corn, and stand it up on your cutting board to cut down the cob, releasing the kernels. Break apart any large clumps.
- Wash the avocados, then cut them in half and discard the pits. Score the flesh into cubes and spoon it out into the bowl with the onion mixture. Squeeze the lime all over the avocado and toss lightly. Use a potato masher or the back of a fork to gently mash the avocado flesh to your desired texture.
- Add most of the corn and cotija to the guacamole bowl and fold or mash to combine. Adjust salt, pepper and lime to taste. Transfer guacamole to a serving bowl and sprinkle remaining corn and cotija on as a garnish.
- Serve immediately with tortilla chips and watch it disappear!