Yellow Squash Casserole

During the peak season, I can’t get enough of summer squash. There are countless ways to enjoy it, but this comforting casserole just might be my favorite. Mixed with sour cream, mayo, cheddar and Parm, this squash casserole is creamy, extra-flavorful, and more than satisfying. Finished with a buttered Ritz cracker topping, this casserole just might be the pinnacle of summer comfort food. Here's how to make it the best it can be:

What People Are Saying:
“Just made it and have to stop myself from eating even more than the two generous servings I’ve already eaten. Thank you for the recipe!” - CyanProcessor

“I’ve been searching for a recipe that would come close to my mother’s squash casserole and I think I found it! This is so good and even better reheated as leftovers!” - Dellydo

How To Make Yellow Squash Casserole

INGREDIENTS

• Butter: This recipe isn’t shy with butter. We’re using it to cook our squash, onion, and garlic, and also to turn our crushed Ritz crackers into a buttery, crumbly topping.
• Yellow Squash: The star of the show is, of course, our yellow squash. I like to slice mine into ½” coins instead of strips so serving the casserole is easier.
• Yellow Onion & Garlic: A chopped yellow onion and two cloves of garlic are small but mighty players in this recipe, adding heaps of flavor to our casserole.
• Cayenne Pepper: If you’re averse to spice, don’t let the addition of cayenne make you nervous. It just helps to amplify our other flavors, and make the casserole a bit more interesting. It’s our main seasoning besides salt and pepper, so I highly recommend using it.
• Eggs: Together with the sour cream and mayo, the eggs will help bind everything together in this casserole, making each bite substantial.
• Sour Cream & Mayo: Hot take: Sour cream and mayo are an iconic combo. In this casserole, they add creaminess, richness, and a little bit of tang.
• Cheddar & Parm: A combination of cheddar and Parm makes this casserole extra cheesy, and pairs so well with the squash—you have to trust me. I highly recommend freshly shredding your cheese for the best possible flavor and texture.
• Ritz Crackers: Ritz crackers are the MVP of casserole toppings, and they create a beautiful golden-brown, crunchy bite to this topping (they just might be my favorite part of this recipe).

STEP-BY-STEP INSTRUCTIONS

First, preheat the oven to 350°, and lightly grease a medium casserole dish. Then, in a large skillet over medium heat, add and melt 2 tablespoons of butter. Add the sliced squash and the chopped onion and cook, making sure you’re stirring often, until the squash is tender. This should take around 8 minutes. Then, add in the garlic, and season with salt, pepper, and cayenne pepper. Once everything is combined, transfer the entire mixture to a colander set over a bowl, and let it drain for 5 minutes. After 5 minutes, discard the excess liquid and set the mixture aside.

In a large bowl, whisk together the eggs, sour cream, and mayonnaise. Then, add the freshly shredded cheddar and Parmesan, and season with salt and pepper. Fold in the squash mixture (do this gently to avoid breaking up the squash), then transfer to your prepared baking dish.

Now, for the topping: Melt the remaining butter, and toss with crushed Ritz crackers in a bowl.

Sprinkle the mixture over the casserole, making sure you cover it evenly. Bake the casserole until the Ritz crackers are golden and the cheese is bubbly, around 20 minutes.

The full list of ingredients and instructions can be found in the recipe below.

Recipe Tips

• How to prevent a watery casserole. Squash is great, but it’s also full of water which can make or break a really lovely meal. However, I incorporated a step into the method to prevent sorrow at the dinner table. After cooking your squash, you're going to transfer your mixture to a strainer or sieve and let it drain for 5 minutes. This will get rid of any extra liquid from sautéing the veggies that would turn your casserole into a watery mess.
• Don’t like yellow squash? More of a zucchini fan? No problem—it will work basically the same. You could even try patty pan squash, mini zucchini, or something sturdier like butternut squash. If you do decide to switch up the squash, keep in mind that with other varieties the textures and cook times will have differing results.

Storage

If you have leftovers, let them cool, then store in the refrigerator in an airtight container for 4 to 5 days.