Marinated veggies are grilled then layered on pesto-slathered buns for the MOST amazing Grilled Vegetable Sandwich! We love these sandwiches in the summer months, but they’re honestly completely craveable year-round.

Grilled Summer Vegetable Sandwiches with Pesto - Summer in a vegan sandwich! Zucchini, summer squash, and red bell pepper doused in balsamic-thyme marinade, grilled to perfection, and then piled onto pesto-smeared artisan rolls.

Table of Contents

The Story Behind the Recipe

Summer arrived remarkably early in the Pacific Northwest, and I’ve been giddily embracing it. Summer is my homeboy. I’ve been loving it so much, in fact, that I had a nightmare last night that suddenly it was mid-November and I looked around, confused – where had summer gone? I cried. Like, actually cried. Well, at least, in my dream I did. Probably into my pillow, too. Luckily, in my dream I remembered that it was still actually July, and I managed to return to summer. Sweet relief.

Good thing, because I’ve got veggies and herbs in the garden, on their way to becoming future summer dinners like this Grilled Vegetable Sandwich. I refuse to skip August, so take that, dream world!

Why You’ll Love These Sandwiches

These Grilled Vegetable Sandwiches take advantage of many of the foodstuffs that summer has to offer. Zucchini, yellow squash, sweet red bell peppers, and handfuls of fresh basil.

The pesto adds tons of flavor and the veggies, with their marinade, are tender and delicious.

Readers say …

“Excellent veggie sandwich! My husband and I loved this!”

– Lisa
Grilled Summer Vegetable Sandwiches with Pesto - Summer in a vegan sandwich! Zucchini, summer squash, and red bell pepper doused in balsamic-thyme marinade, grilled to perfection, and then piled onto pesto-smeared artisan rolls.

Ingredients

  • Zucchini & yellow squash – You can use all zucchini or all yellow squash, I just like the slightly different flavors and pretty colors.
  • Red bell pepper
  • Ciabatta sandwich rolls – Any favorite artisan sandwich roll will work, or one reader reported using focaccia which I think sounds absolutely amazing!
  • Olive oil – For toasting the rolls & for the veggie marinade
  • Pesto – For slathering on the rolls. Use your favorite store-bought brand or recipe, or try one of my favorite pesto recipes
  • Garlic, balsamic, thyme, Dijon mustard, lemon zest, salt & pepper – for the veggie marinade. YUM.

Adaptations/Variations

  • Keep it vegan by using vegan pesto. I’m pretty partial to this homemade vegan pesto recipe!
  • One Dish Two Ways for vegetarians and meat-eaters living together: Sandwiches are great for customizing to individual tastes and diets because of their handy-dandy individual serving size. My carnivorous guy tried these with a grilled chicken sausage sliced lengthwise and tucked inside but actually decided he preferred it without because it was so flavorful already. Perhaps some grilled sliced chicken breast would work nicely.
  • Make it cheesy by adding a melty slice of provolone, coins of fresh mozzarella, or a smear of herbed goat cheese. Grilled halloumi is amazing on these sandwiches, too!

How to Make Grilled Vegetable Sandwiches

To make them, you first give the veggies a quick soak in a balsamic-thyme marinade. While they marinate, if you’re using homemade pesto, go ahead and whip that up.

Grill the veggies either on your barbecue or indoors on your grill pan, then slather the insides of crusty toasted rolls with the fresh pesto.

Layer the veggies inside, and you’re good to go.

Grilled Summer Vegetable Sandwiches with Pesto - Summer in a vegan sandwich! Zucchini, summer squash, and red bell pepper doused in balsamic-thyme marinade, grilled to perfection, and then piled onto pesto-smeared artisan rolls.

Tips for Success

  • Toast your rolls. The crisp, golden insides hold up well to the pesto, and the added crunch and flavor is perfect!
  • Don’t flip your veggies too soon. Let them sit for awhile on the grill so that they form those glorious grill marks (this is where the flavor lies, too!)

More Grilling Recipes

More Vegetarian Sandwich Recipes

5 from 1 vote

Grilled Vegetable Sandwich

Prep: 40 minutes
Cook: 10 minutes
Total: 50 minutes
Author: Kare
Yield: 4 sandwiches
Summer in a sandwich! Zucchini, summer squash, and red bell peppers doused in balsamic-thyme marinade, grilled to perfection, and then piled onto pesto-smeared artisan rolls.
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Ingredients

  • 2-3 small to medium zucchini (1 pound)
  • 2-3 small to medium summer squash or yellow squash (1 pound)
  • 1 large red bell pepper
  • 4 ciabatta sandwich rolls (or your favorite artisan sandwich roll)
  • 2 tablespoons olive oil
  • 1/2 cup pesto

Marinade:

  • 1/4 cup olive oil
  • 2 medium cloves garlic (minced)
  • 2 tablespoons balsamic vinegar
  • 2 teaspoons fresh thyme leaves (chopped)
  • 1 teaspoon Dijon mustard
  • Zest from one lemon
  • 1/2 teaspoon kosher salt + more to taste
  • 1/8 teaspoon freshly ground black pepper + more to taste

Instructions

  • Slice the zucchini and summer squash lengthwise, 1/4- to 1/2-inch thick. Cut the bell pepper into 1-inch wide strips. Lay in a roomy baking dish.
  • Make the marinade. In a small bowl, whisk together all marinade ingredients. Taste and add additional salt and pepper if desired. Pour over the veggies and toss gently. Let sit for about 30 minutes.
  • Prepare your grill – medium direct heat, about 375 degrees. Lay the vegetables on the preheated grill grates and cook until grill lines form, about 5 minutes. Flip (we like to use long-handled tongs) and cook on the other side until tender and cooked through, about 5 more minutes. Transfer from the grill to a platter. Keep the grill on to quickly toast the rolls.
  • Slice the rolls in half and brush the insides with the 2 tablespoons olive oil. Lay the rolls cut-side down on the grill and cook just until warmed and a little golden and toasty. Remove from grill.
  • Assemble the sandwiches. Smear both sides of the roll with approx. 1 tablespoon of pesto on each side (more or less to taste). Add a layer of zucchini, summer squash, and two or three strips of the pepper. Close, cut in half, and serve!

Notes

Vegetarian options:

  • If you prefer Parmesan in your pesto, add 2 tablespoons to 1/4 cup shredded, to taste.
  • Add a slice of provolone to your sandwich or smear the roll with a little herbed goat cheese.

Meat options:

  • Add a layer of grilled chicken or a few slices of your favorite sausage.
6/10/2024 recipe update: Removed pesto recipe and instead called for your favorite pesto for simplification. If you’re still looking for the pesto recipe, here it is:
Basil Walnut Pesto
1/3 cup walnuts (toasted)
3 cups fresh basil (loosely packed)
2 medium cloves garlic (minced)
2 tablespoons fresh thyme leaves
1 tablespoon fresh lemon juice
1/2 teaspoon salt
2 tablespoons nutritional yeast flakes or Parm
1/3 cup olive oil
First, toast the walnuts (an optional but worthwhile step – toasting adds wonderful flavor). To toast, set a small pan over medium heat and add the walnuts. Stir frequently until golden and fragrant, about 5 minutes. Add to the pitcher of a blender or a food processor fitted with the s-blade. Add the basil, garlic, thyme, lemon juice, nutritional yeast or Parmesan if using, and salt. Turn on the blender or food processor, streaming in the olive oil as it runs, until a sauce forms. Taste pesto and add additional salt if desired.

Nutrition Facts

Serving: 1sandwich, Calories: 481kcal, Carbohydrates: 39g, Protein: 9g, Fat: 33g, Saturated Fat: 5g, Polyunsaturated Fat: 2g, Monounsaturated Fat: 15g, Cholesterol: 2mg, Sodium: 882mg, Potassium: 599mg, Fiber: 4g, Sugar: 8g, Vitamin A: 1997IU, Vitamin C: 74mg, Calcium: 93mg, Iron: 1mg

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