Pasta salads pop up in my meal plans on hot summer evenings and linger well into the fall. Through September and October, my whole family looks forward to this pesto pasta salad with roasted vegetables. It’s a quick and easy way to use the last few summer squash and tomatoes from my vegetable garden.

This recipe for pesto pasta salad may be new to this blog, but it’s hardly new to our household. It’s long been a fall staple for my family, initially for busy evenings driving kids around to soccer practice. I’d toss in some grilled chicken and it was a good, filling, healthy dinner for my girls to eat on the go. But even though that part of my life is long gone, this recipe for pesto pasta salad with roasted vegetables has stuck around. It shows up frequently on warmer fall nights and is always asked for at our friends' UW Husky tailgate parties.
I’ve included a recipe for walnut pesto to dress this pasta salad with, but you can use any pesto you want, including store-bought. My recipe for macadamia nut pesto is a delicious option too. If your pesto seems too thick, you can thin it with a bit of olive oil, lemon juice or red wine vinegar. My family especially likes this salad with a bit of a lemony kick, which brightens up the whole dish.

Is pasta salad healthy?
This is a good question, actually, and since I write a blog about eating healthier, I feel I should answer it. As is common with good questions about complex topics, the answer is, “it depends.” Whole grain bread and pasta are very much part of a healthy, balanced diet, but like most things, are better consumed in moderation. If your pasta salad is loaded with mayo and cheese and very little veg, then it’s probably not healthy. But I’ve found a few tricks to make pasta salads as healthy as they can be.
- Less pasta, more veg - changing the ratio of pasta and vegetables is the best way to make a pasta salad healthier and more nutritious. I use only 2 cups of pasta in this recipe (this is the uncooked measure, it’s about 4 cups cooked). You could get away with using even less.
- Use whole grain pasta - I don’t generally love whole grain pasta, but I also don’t usually notice any difference in pasta salads. This makes it a great opportunity to get some high fiber whole grains into your family’s diet without hearing complaints from the peanut gallery.
- Dress with a vinaigrette or pesto - Creamy mayo or dairy-based pasta salad dressings pile on the fat, and not in a good way. I usually opt for herby vinaigrette or pesto to dress my pasta salad.
Ingredients and substitutions
For the pasta salad:

Cherry tomatoes - We’ll be roasting these, so it’s a good use for cherry tomatoes from the garden that are a little past their prime. Save the perfect ones for popping into your mouth.
Zucchini and yellow summer squash - If you prefer, you can sprinkle the zucchini and yellow squash with ½ teaspoon kosher salt and set it aside to drain excess moisture for 15-20 minutes. It helps keep them a little more crisp-tender after cooking.
Red bell pepper - Yellow and orange peppers also work here.
Red onion - I prefer red onions here because they roast up sweet and look beautiful in this pasta salad, but it’s fine to use whatever you have on hand.
Extra virgin olive oil - I use Kirkland Signature Organic Extra Virgin Olive Oil.
Salt and pepper - I test my recipes with Morton’s kosher salt unless otherwise noted.
Whole grain spiral pasta - I typically use Barilla pasta. For a gluten free option, you can use an alternative pasta such as Banza.
Fresh mozzarella - Costco has great prices on fresh mozzarella! You can cut it yourself or buy the tiny balls of mozzarella, called cigliene.
For the walnut pesto:

NOTE: Store-bought pesto works absolutely fine in this recipe!
Basil leaves - pull the leaves off the stems, which can be bitter.
Garlic - please use fresh garlic when you are making pesto. There’s no substitute!
Parmesan cheese - Parm, romano, asiago…any sharp aged crumbly cheese will work. Grate or shred it yourself if you have the option.
Walnuts - Whole walnuts or walnut pieces work. You can also use pine nuts or macadamia nuts if that's what you have on hand.
EVOO - It’s extra yummy to blend in a couple of tablespoons of walnut oil if you have some on hand.
Fresh lemon juice - About 1 lemon worth of juice. If you don’t have fresh lemon juice, leave it out. The bottled variety is too acidic.
Kosher salt - I test my recipes with Morton’s kosher salt unless otherwise noted.
FAQ: Walnut pesto pasta salad with roasted vegetables
Pasta gets sticky from the starches that are released during cooking. Overcooking is the surest way to get sticky pasta, so you want to be sure to check your pasta for doneness early and often.
Aside from that, there are several cooking strategies to prevent sticky pasta. Firstly, you’ll want to cook your pasta in plenty of water so that the released starch doesn’t become too concentrated. Make sure to add the pasta to water that is fully boiling, not just simmering, so that it cooks fast enough and doesn’t release too much starch. And be sure to stir your pasta frequently while it cooks, especially in the first few minutes. This moves the starch out into the water, away from the surface of your pasta.
For any cold pasta dish, rinse your pasta in cool water immediately after draining, just enough to cool it down from cooking temperature. This will rinse some of the starch off the surface of the pasta and prevent it from clumping together.
Technically, everything is allowed on the Mediterranean diet. So yes, as long as you keep your ratio of carbohydrates to protein and fats consistent, you can eat pasta while you are on the Mediterranean diet. Selecting whole grain pasta boosts both the fiber content and the overall nutrition of the pasta and helps control blood sugar and increase satiety. The key is to watch the ratios on your plate so that the vegetables still take center stage.
Any vegetable you can roast can go in this salad! Broccoli, asparagus, green beans, and corn are just a few of the ideas that come immediately to mind. Eggplant, mushrooms, cauliflower, and carrots are also delicious. The sky is the limit!

Tips for the perfect walnut pesto pasta salad with roasted vegetables
Don’t let your pasta get sticky: Cook your pasta in plenty of salted water, making sure that it’s boiling before you add your noodles. Stir the pasta frequently while it’s cooking. See the FAQ for more details!
Cook your pasta until it’s done: Because we will be cooling the pasta down quickly with a rinse after we drain it, you don’t want to leave it too al dente, as you would if it was going to cook further in a sauce. But don't cook it longer than recommended!
For perfectly cooked vegetables, cool them down quickly: You want to keep your veggies a little crisp-tender, so it’s important to get them off your sheet pan ASAP after they come out of the oven. I scoop them into a shallow heat-proof bowl and spread them out a bit so they can cool down faster.
It's easy to customize this recipe!
Make it a main dish: Add chopped rotisserie or grilled chicken or leftover grilled salmon.
Make it gluten-free: Use gluten free chickpea pasta such as Banza.
Make it vegan: Omit the mozzarella cheese and the pesto and toss your pasta salad with vegan Parmesan cheese and a simple balsamic vinaigrette.

Prep ahead and storage
This walnut pesto pasta salad can be made and assembled ahead of time. If it’s going to be more than a couple of hours, however, I find it keeps better if you keep the pasta and the pesto-coated roasted vegetables separate.
Keep any leftovers in a sealed container in the refrigerator for up to 3 days.
Did You Make This Recipe?
If you make this walnut pesto pasta with roasted vegetables, I’d love to hear what you think. I am always trying to get better at developing recipes, and your feedback helps me do that.
Don’t forget to tag me on Instagram (@parsleyandparm) and use #YourHashtag. I love seeing your creations!
Walnut Pesto Pasta Salad With Roasted Vegetables
Equipment
- Knife and cutting board
- Rimmed sheet pan
- Spatula for turning vegetables
- Medium saucepot for cooking pasta
- Colander or sieve
- Large salad bowl
Ingredients
For the pasta salad:
- 1 medium zucchini
- 1 yellow summer squash
- 2 red bell peppers
- ½ red onion
- 2 cups cherry tomatoes
- 2 tablespoons extra virgin olive oil
- ½ teaspoon salt
- pepper to taste
- 2 cups whole grain spiral pasta
- 1 cup fresh mozzarella ¼-inch dice
For the walnut pesto (store-bought pesto works great too):
- ¼ cup parmesan cheese grated
- ¼ cup walnuts whole or pieces
- 2 cloves garlic
- ½ teaspoon fine sea salt
- 2 cups fresh basil leaves
- ½ cup extra virgin olive oil
- 2 tablespoons fresh lemon juice fresh only!
Instructions
Prep your ingredients:
- Preheat your oven to 400 degrees and put on a large pot of water to boil.
- Cut the zucchini and yellow squash in half lengthwise, and slice into ½ inch thick half moons.1 medium zucchini, 1 yellow summer squash
- Chop the bell pepper and red onion into ½ inch pieces and halve your tomatoes.2 cups cherry tomatoes, 2 red bell peppers, ½ red onion
- Wash and dry your basil and set aside.2 cups fresh basil leaves
Roast the vegetables:
- Add the zucchini, yellow squash, bell pepper, and onion pieces to a rimmed baking sheet and drizzle with olive oil, salt, and cracked black pepper. Toss everything together with a spatula, spread it out in a single layer, then roast for 10 minutes.2 tablespoons extra virgin olive oil, ½ teaspoon salt, pepper to taste
- After 10 minutes, remove the pan from the oven and use your spatula to give it a good stir. Add the cherry tomatoes over the top and return to the oven for 5 more minutes.
While the veggies are roasting:
- Salt your boiling water generously and cook the pasta according to the directions on the box. Drain and rinse briefly with cold water to cool the pasta, then set aside.2 cups whole grain spiral pasta
- Add the parmesan, walnuts, garlic, and salt to your food processor. Pulse 7-8 times to chop the garlic and walnuts.2 cloves garlic, ¼ cup parmesan cheese, ¼ cup walnuts, ½ teaspoon fine sea salt
- Add the basil to the walnut mixture and pulse 7-8 more times to chop the herb.2 cups fresh basil leaves
- Add the olive oil and lemon juice and pulse until the pesto resembles a puree.½ cup extra virgin olive oil, 2 tablespoons fresh lemon juice
- Taste the pesto and add more salt by the pinch as needed, stirring well in between pinches. You want it to be well-seasoned.
Cool the vegetables
- Remove the vegetables from the oven and transfer them to a heat-proof bowl immediately. Spread them out as much as possible in the bowl and allow them to cool for about 5 minutes, then toss them with the pesto.
- Let this mixture to cool on the counter for another 10 or so minutes, then toss with the pasta and place the bowl in the refrigerator for another 20-30 minutes until cool.
Finish and serve:
- Add the mozzarella balls and toss well to combine. Taste and season with salt and pepper if needed. I like this recipe with lots of pepper, but that’s just me!1 cup fresh mozzarella
- Garnish with extra basil leaves if desired, and serve.
Notes
Need more servings?
To adjust a recipe for more or fewer servings, hover your cursor over the number servings on the recipe card. This will bring up a slider that you can move to the number of servings you want to make.
Nutrition*
*All nutritional values are estimates only. They are calculated by an online resource.
Kelly says
This is literally the perfect potluck dish!
Erica says
loved it!
Susan Colts says
I love walnut pesto. I needed new ways to use it. Thanks.