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This healthy yellow squash casserole is so delicious and the perfect comfort food to make for your family any time of year!

Does anyone hear the word casserole and think of their grandma? Maybe it’s just us, but our grandma would always make a casserole for large gatherings. Sometimes it wasn’t just one casserole, more often than not, she made several casseroles for a meal with family.

One of the casseroles she has made the most over the years is her squash casserole. It’s always a crowd favorite and tastes so delicious! We wanted to make a healthier twist on her squash casserole, but still make it taste just as good as hers.

Made with slowly caramelized onions, sautéed yellow squash, creamy greek yogurt, avocado mayo, panko bread crumbs and a little bit of Parmesan cheese. This healthy yellow squash casserole is super delicious and reminds us so much of our grandma’s original recipe (but healthier)!

This post is all about healthy yellow squash casserole.

Healthy Yellow Squash Casserole

What’s in this recipe?

Yellow Squash: The squash is the star of the show and there’s a lot of it! Yellow squash is one of our favorite vegetables and tastes so delicious in this casserole.

Garlic: Fresh minced garlic adds such a delicious flavor to this dish.

Yellow Onion: Yellow onion is sweeter than a purple onion, and provides a rich flavor when it’s sautéed and caramelized.

Chicken Broth: Not only does the chicken broth add some moisture to this casserole, but it gives the dish a delicious flavor.

Greek Yogurt: Most squash casseroles are made with sour cream and other heavy creams. Greek yogurt is a healthier alternative to sour cream, while still giving this dish a tang and creaminess.

Avocado Mayo: Avocado mayo is so delicious and good for you. A heaping spoonful of this avocado mayo adds more depth of flavor.

Parmesan Cheese: Many times, casserole recipes can go overboard with the amount of cheese they put in a recipe. We wanted to keep this dish light, so adding a cup of Parmesan cheese to the dish was the perfect amount.

Panko Bread Crumbs: We absolutely love Panko bread crumbs! They are a healthy alternative and create a delicious crunchy texture.

Egg: The egg helps to find the ingredients together.

Italian Seasoning: Italian seasoning adds beautiful flavor to this casserole.

Salt and Pepper: Salt and pepper is always a must!

How to Make the Yellow Squash Casserole

This casserole is super simple to make! It’s only a few simple steps of sautéing, mixing and baking.

Step one is to prep all the vegetables to cook. We sliced the our squash, diced our yellow onion and minced the garlic cloves.

Next, you’ll need a dutch oven to sauté the vegetables. This is the one we used and is super affordable and is comparable quality to our other Le Cruset dutch ovens. In whatever dutch oven or pan you are using, add a tablespoon of olive oil to the pot. Add your sliced squash and sauté for 5-7 minutes. After the squash has started to soften some more, transfer the squash to a colander. This will let the extra liquid from the squash to drain.

In the same dutch oven, add chicken broth, onion, salt and pepper. Sauté the onions until they look translucent. Then, add your minced garlic and sauté for about one more minute. If you cook the garlic too long, it will begin to burn, so adding it in at the end is key.

In a small mixing bowl, combine the greek yogurt, avocado mayo, 1/2 cup of Parmesan cheese, 1/2 cup of panko bread crumbs, italian seasoning, salt and pepper and the beaten egg. Mix these ingredients until they are completely combined.

Then, add the squash, onion and the greek yogurt mixture until the squash it coated. We like to use our hands to mix and coat the squash completely.

Lastly, pour the mixture in a casserole dish (this is the one we used and the one in our picture). Top with the rest of the panko bread crumbs and Parmesan cheese.