It should be easy. Herbs, nuts, cheese, oil, blend. But for some reason, pesto has always been a tricky sauce for me to get right. That is, until I made this creamy, delicious, perfect Spicy Pesto Pasta recipe (again and again and again).
Sometimes the herbs taste too earthy or turn brownish as soon as they touch the hot pasta. Sometimes it looks right and tastes fine but it’s missing a little oomph. And then there’s the question of how much cheese and what type of nut and when do I add the oil?
So if you’ve ever struggled with perfecting your pesto, you’re not alone. Maybe I’m alone. Either way, here are a few things that make this vibrant, vegetarian dinner so great:
The right amount of basil. I used to think pesto was all about packing in as many herbs as possible into a blender (especially if you’re desperately trying to use up the haul from your garden), but I’d encourage restraint. Too many herbs can cause the sauce to taste like it came straight from the ground, and while that might be nice for a rabbit, a pesto for humans is all about balance. I landed on a moderate 2 cups of lightly packed basil, or about 1 ounce.
Blanch the basil. To prevent the basil from turning brown as it hits the hot pasta (when chopped basil is exposed to air, it will oxidize), boil it for a few seconds and then shock it in ice water to lock in that bright green color. You’ve already got boiling water for the pasta, so I don’t find this step too fussy.
Walnuts. This is my preferred nut for pesto. It’s super buttery and contributes creaminess without the price tag of the classic pine nut.
More cheese, please. I grew up eating Kirkland Signature Basil Pesto (one of Costco’s finest products) which tastes like it’s about 90% cheese. I wanted that same delicious richness… just dialed back a bit. Two ounces or about ½ cup is a happy medium.
Spice and acid. These two elements are generally missing from pesto, and while the sauce doesn’t necessarily need them, I think it can always benefit from a little lift. Jalapeño and red pepper flakes add heat and fresh lemon juice adds zest that cuts through the richness of the aforementioned nuts and cheese. These are the special ingredients that really make the sauce sing.
Not interested in a vegetarian dinner? Sear some chicken cutlets as the pasta boils to make a hearty, spicy chicken pesto pasta.
Clearly, there are a lot of questions about how to make the best pesto ever. Now that you’ve got the answers, let’s dive in:
How To Make Spicy Pesto Pasta

First, blanch the basil and boil the pasta. Reserve 1 cup of the pasta cooking water, drain, and return the pasta to the pot.
Next, char the jalapeño: If you have a gas stove, hold the pepper with heat-safe tongs 1-2 inches over an open flame set to medium, turning until the skin is charred all over, about 2 minutes. If you have an electric stove, set your broiler to high. Cut the jalapeño in half lengthwise and remove the seeds. Place each jalapeño half, cut side down, skin side up on a small baking sheet, 3-4 inches from the broiler. Broil the pepper until charred, 3-4 minutes. For either method, immediately transfer the pepper to a heat-safe container (like Tupperware) and close the lid so it can steam. Let it steam for 3-5 minutes while you prep other ingredients.

To a blender, add walnuts, cheese, garlic, red pepper flakes, lemon juice, and oil. When the jalapeño is tender, and cool enough to handle, peel the skin off (it should come off easily) and discard. Chop off the stem and discard. Taste a bit of the jalapeño to determine its spiciness, then add as much as you’d like to the blender (I usually add the whole thing, seeds and all).

Blend until smooth, about 1 minute. Use a spatula to scrape down the sides of the blender, then add the basil. Blend until smooth and creamy, about 1 minute more. Taste and add salt or additional red pepper flakes or lemon if needed.

Add the pesto to the pasta with a splash of the reserved pasta water and the butter, if using, and stir vigorously until the pesto evenly clings to the pasta, about 2 minutes, adding more water if the pasta seems dry. Taste and add more salt, red pepper flakes, or lemon if needed. Serve right away.

What To Serve with Spicy Pesto Pasta
10-Minute Baked Sheet Pan Fish
Lemon Artichoke Chicken Skillet
This creamy and delicious pasta stars red pepper flakes, jalapeño, and lemon juice for a next-level sauce that shines. Blanch the basil: Bring a large pot of water to boil and salt generously. Set a small bowl of ice water next to it. Add the basil and cook for 5 seconds, then use a slotted spoon, a spider, or a small colander to remove the basil and transfer it to the ice water. Set aside until ready to use. Add the pasta to the now-empty boiling water and cook according to package directions. Reserve 1 cup of the pasta cooking water, drain, and return the pasta to the pot. Char the jalapeño: If you have a gas stove, hold the pepper with heat-safe tongs 1-2 inches over an open flame set to medium, turning until the skin is charred all over, about 2 minutes. If you have an electric stove, set your broiler to high. Cut the jalapeño in half lengthwise. Place each jalapeño half, cut side down, skin side up on a small baking sheet, 3-4 inches from the broiler. Broil the pepper until charred, 3-4 minutes. For either method, immediately transfer the pepper to a heat-safe container (like Tupperware) and close the lid so it can steam. Let it steam for 3-5 minutes while you prep other ingredients. To a blender, add walnuts, cheese, garlic, red pepper flakes, lemon juice, and oil. When the jalapeño is tender, and cool enough to handle, peel the skin off (or scrape it off with a small knife) and discard. Chop off the stem and discard. Taste a bit of the jalapeño to determine its spiciness, then add as much as you’d like to the blender (I usually add the whole thing, seeds and all). Blend until smooth, about 1 minute. You can add a splash of pasta water to get the blender going if needed. Use a spatula to scrape down the sides of the blender, then add the basil. Blend until smooth and creamy, about 1 minute more. Taste and add salt or additional red pepper flakes or lemon if needed. Add the pesto to the pasta with a splash of the reserved pasta water and the butter, if using, and stir vigorously until the pesto evenly clings to the pasta, about 2 minutes, adding more water if the pasta seems dry. Taste and add more salt, red pepper flakes, or lemon if needed. Enjoy! Every jalapeño has a different level of spiciness — some are super-spicy, others are almost completely mild — so it's important to taste a bit of the jalapeño before adding it to the blender.
If your blender overheats, your sauce may break. If this happens, don't panic! Just let the blender cool for a minute and add a splash of cold water and blend again.Spicy Pesto Pasta
Ingredients
Instructions
Notes
2 Comments
Timothy
July 22, 2022 at 8:40 amHello AHC, this is to die for! thank you 🙂
Samantha
July 23, 2022 at 8:31 amThank YOU!