This roasted butternut squash sandwich with caramelized onion and pesto is a super easy recipe to make when winter squash is abundant. It is excellent for a healthy meatless lunch or dinner.

a slice of roasted butter squash sandwich with caramelized onions and pesto

This recipe is my version of the sandwich I used to love at a store near my old workplace. Nowadays, I enjoy making it at home (besides this pumpkin soup and pumpkin fritters with salted egg yolk sauce) when winter squash is in season. It is easy to make, and there are several ways to customize it to your liking.

Ingredients

Here are the main ingredients you’ll need for this recipe:

butternut squash: I haven’t tried making this sandwich with other types of cooking squash. If you try other squashes, please feel free to comment.
bread: I often use ciabatta. Baguette, hoagie roll or your other favorite bread for sandwich will work too.
caramelized onions: these are sliced onions that are cooked on the stove gradually until caramelized, soft and sweet.
pesto: it adds a pleasant herby fragrance to the sandwich. If you want to keep the sandwich vegetarian/vegan, please use vegetarian/vegan pesto.

plates with sliced butternut squash and onions

Optional Add-ins

You can customize this roasted butternut squash sandwich by adding more filling, for example:

cheese
arugula
other roasted veggies such as zucchini or eggplant

An Easy Meatless Sandwich for Fall and Winter

This easy sandwich recipe has two main steps, which are not quick but fairly straightforward. The first step is roasting the butternut squash. Simply slice the squash thinly, and toss with salt, pepper and oil. You can also add some dried herbs if desired. Then bake in the oven until tender. Try to keep the squash slices at a similar thickness so that they will cook evenly.

roasted butternut squash slices on a baking sheet

While roasting the squash, you can caramelize the onions, which does require some time and patience. You will need to cook the onions gradually to deepen the color, flavor and sweetness. I like to start with cooking them in olive oil over medium heat, and then reduce the heat as needed. Halfway through the process, it is time to add some butter and continue to cook until your desired level of caramelization is reached.

I don’t think it is necessary to cook them very dark. I prefer a lighter level of caramelization as in the photo above, which ensures no unpleasant bitterness as well as saves up some cooking time.

Once these two components are ready, you can assemble the sandwich pretty quickly. I like to have the bread toasted for some extra crunch. I look forward to hearing how you make this roasted butternut squash sandwich recipe.

If you need more some fun ideas for what to make with bread, also give these baked shrimp toast and slow cooker pulled pork banh mi a try.

a tray of roasted butternut squash sandwiches with salad on the side

⭐️ I’d love to hear what you think about the dish, so please feel free to leave a comment and a rating if you have tried it. New recipes are added every week so let’s connect on Facebook, Youtube, Pinterest and Instagram for the latest updates. You can find my collection of Vietnamese recipes here.