I was scrolling mindlessly through Instagram a few weeks back when I stumbled across a reel of Mob making this recipe for melted leek pesto pasta. Just by watching a few seconds of the video, I knew I had to make this recipe for myself — I had never tried to confit anything before. Well, reader, the effect is as delicious as slow-cooking something in butter. And that is not a compliment I pass out lightly.
The French term confit is traditionally applied to the culinary practice of cooking meat (like duck or pork) in its own fat, but it can also refer to cooking fruit or vegetables in seasoned liquid until tender. Netizens of social media have undoubtedly encountered video after video of garlic confit, which simply entails slow-cooking garlic in oil that's been seasoned with herbs or chili flakes.
This recipe takes a similar approach. If you have the time to slow-cook something on the stove, let it cool, and blend it up, you're in for a silky, nutty, creamy, and utterly delicious leek and walnut pesto.
"But it's not a pesto!" I hear the puritans cry, clutching their pestle and mortars to their chests. I know it's not a pesto. It's a blended sauce. But nobody is Googling "blended sauce pasta recipe", so you'll have to air your grievances with our SEO team.
What you'll need from the shops for this leek and walnut pesto pasta recipe
Head of garlic
Parmesan (if you can spring for the proper Parmigiano Reggiano, it makes a difference)
How to make leek and walnut pesto pasta
Step One: Prep your kak
You'll start by roughly chopping your leeks and peeling your garlic cloves until you have as many as your heart desires (I typically go for just over half a head). Don't fret about aesthetics, it's all going to be blended up anyway.
Step Two: Confit the leek and garlic
Once that's done, and if you're confident in your multitasking abilities, tip your chopped leek and peeled garlic into a heavy-bottomed pot or pan. Cast iron or stainless steel are a good bet if you have one lying around. Then, pour enough oil into the vessel to comfortably cover the vegetables.
Next, set the heat to low-medium and let the oil do its magic. It will take about thirty to forty minutes for the confit vegetables to soften and darken in colour. Your kitchen will smell magnificent.
Step Three: Toast the walnuts
While the vegetables are slowly cooking in an aromatic oil bath, you can toast your walnuts. Simply set them in a pan, put them on medium heat, and toss them regularly until you get an even brown on every side and the nut turns from soft to slightly crisp and aromatic. Do not turn your back for even a second — those nuts can burn in a second. Once they start to smell really nutty, toss them into a bowl to stop the cooking process.
Step Four: Blend
Unless you have a heatproof food processor, I would strongly recommend that you take your confit off the heat and let it cool for a good while before blending. If you have a flip blender like a Nutribullet, then this is a safety precaution. Blending hot foods causes immense steam pressure, which can result in an explosion of hot pesto on an unfortunate bystander (i.e., you).
Anyway, once your confit is at a non-lethal temperature, chuck it in your blender with the toasted walnuts and about half of the Parmigiano Reggiano triangle broken up into smaller pieces. Reserve some of the aromatic oil — you can add more liquid to a chunky pesto, but you cannot undo an accidental leek smoothie.
Okay, now blend! If the mixture is too claggy, add more oil. We're looking for a relatively smooth mixture that is closer to paste consistency than liquid consistency.
Step Five: Combine with pasta
Sadly, load shedding meant that I could not photograph this step, but I'm confident in your ability to imagine what it looks like to cook pasta. This "pesto" really comes alive when you add a spoonful or so of pasta water to it, so keep that in mind if you're worried about the paste-like consistency. A splash of starchy water will ensure a beautifully silky, creamy sauce that sticks to the pasta and impresses literally everyone (including yourself).