Save This Recipe
We'll email this post to you, so you can come back to it later!
A golden, cheesy, Southern classic with a weeknight-friendly twist
Let me paint you a picture.
It was a Tuesday. Not a holiday, not a gathering—just one of those regular, slow-moving summer days. I had squash practically spilling off the counter because my neighbor keeps dropping off baskets from her garden like I’m feeding a small army. Sweet of her, truly. But I was fresh outta ideas and in no mood to wrestle with a deep casserole dish.
I remembered how my mama used to make squash casserole in her big old Pyrex—rich, cheesy, topped with those buttery crackers. The smell would fill the whole house. But I wanted something easier. Flatter. More bite-sized. And that’s when it hit me—sheet pan style. Just enough golden edges, easy to slice, no digging involved.
I threw it together without a second thought. And you know what? It ended up being the best dang version I’ve ever had. We ate half the pan standing over the stove.
So… why’ll you love this?
-
It’s cheesy and crispy in all the right places – That combo of melted cheddar and buttery cracker crunch? Mercy.
-
Perfect for sharing (or not) – Slices up neat, makes a big batch, reheats like a dream.
-
Way easier than traditional casserole – One sheet pan, no fuss, no deep dish.
-
It tastes like home – The kind of thing that makes you want seconds before you’ve finished firsts.
What you’ll need (and what you can swap if needed)
You don’t need anything fancy. In fact, you probably already have half this stuff in your fridge.
-
2 lbs summer squash: Yellow squash is ideal, but zucchini will do fine. If they’re oversized and seedy, scrape those seeds out. Keep the slices about ¼-inch thick so they cook evenly.
-
½ yellow onion: Gives it that little savory something. If raw onion isn’t your thing, you can sauté it first—or skip it altogether, though I think you’d miss it.
-
1 sleeve butter crackers: Ritz-style. No need to crush them for the bottom layer—they go down whole like a buttery little floor for the squash to sit on.
-
Cheddar cheese: Four and a half cups sounds like a lot. That’s because it is. And it’s glorious. I like sharp cheddar because it cuts through all the creamy goodness, but use what you like.
-
Sour cream + mayo: Yes, both. It’s not too much, I promise. Together they make the casserole creamy without being gloopy.
-
Heavy cream: Makes it lush. Half-and-half is a decent stand-in, but whole milk won’t give you that same silky texture.
-
Eggs: Two of ’em, beaten. Helps everything set up nicely.
-
Garlic powder + pepper + salt: Not too much—just enough to keep things interesting.
-
Extra crackers + butter for topping: Because golden crunch is what brings it all home.
How to make it — real easy-like
1. Preheat and prep.
Set your oven to 350°F. Spray a rimmed 10×15-inch baking sheet with nonstick spray—get the corners good.
2. Boil the squash and onions.
Toss the sliced squash, chopped onion, 5 cups of water, and 1 teaspoon of salt in a big pot. Bring it to a boil, then simmer till tender—about 7 minutes. Drain it well, then let it sit a minute. You don’t want that water dragging down your casserole.
3. Start the base.
Line your sheet pan with the sleeve of butter crackers—just lay them out like little shingles. Sprinkle 3½ cups of shredded cheddar all over. Pop that in the oven for 5 minutes, just to melt it. Trust me, that cheesy base makes the whole dish sing.
4. Make the creamy stuff.
In a bowl, whisk together sour cream, mayo, heavy cream, garlic powder, pepper, the rest of your salt, and the beaten eggs. It’ll look like something from grandma’s church cookbook. That’s how you know it’s right.
5. Layer and pour.
Spread the squash over the cheesy cracker base. Take your time. Then slowly pour that creamy egg mixture over the top. You don’t want to flood it—just pour gently and evenly.
6. Top it off.
Sprinkle on the rest of your cheddar, then mix the crushed crackers with melted butter and scatter that over everything.
7. Bake and cool.
Bake for about 25 minutes, or until the center is set and the top’s a little golden. Let it cool at least 20 minutes before cutting into it. I know—it smells amazing. But letting it rest makes a world of difference.
Little extras & twists
Feeling adventurous? Here’s how you can make it your own:
-
Add a handful of cooked bacon or ham if you want something heartier.
-
Toss in a pinch of cayenne or smoked paprika for a hint of heat.
-
Swap half the cheddar for Monterey Jack if you want it extra melty.
-
Use crushed potato chips instead of crackers if you’re in a pinch (don’t knock it till you try it).
Storing and warming it back up
This dish might even be better the next day.
-
Store leftovers in the fridge for up to 4 days, covered tight.
-
Reheat in the oven at 300°F for about 10-12 minutes, or in the microwave for a minute or two.
-
Don’t freeze it. The squash and creamy filling just don’t love the freezer. Gets kind of weepy, you know?
Just one last bite…
I didn’t expect this sheet pan squash casserole to become a regular at my table. But it’s that kind of dish—the one you make once, then again two weeks later, then again for a potluck, and suddenly your friends are texting for the recipe.
It’s simple. It’s cozy. It feels like something your aunt would bring to a reunion and someone else would sneak a second helping before the blessing’s even done.
If you make it, I’d truly love to hear how it turns out. Did you use zucchini? Did your husband ask for seconds? Did the kids eat it without asking what was in it? Send a note or leave a comment—I always read every one.
And hey, save me a corner piece.
Sheet Pan Squash Casserole
Ingredients
- 2 lbs summer squash, sliced 1/4-inch thick
- 5 cups water
- 1/2 medium yellow onion, chopped
- 1 3/4 teaspoons salt, divided
- 1 sleeve butter crackers
- 4 1/2 cups Cheddar cheese, grated and divided
- 2/3 cup sour cream
- 2/3 cup mayonnaise
- 1/4 cup heavy whipping cream
- 1/2 teaspoon garlic powder
- 1/4 teaspoon black pepper
- 2 large eggs, beaten
- 1 cup butter crackers, crushed
- 1 tablespoon unsalted butter, melted
Instructions
- Preheat oven to 350°F and spray a 10x15-inch rimmed baking sheet with nonstick spray.
- In a large pot or Dutch oven, bring squash, water, onion, and 1 teaspoon of salt to a boil over medium-high heat. Reduce heat and simmer until tender, about 7 minutes. Drain and set aside.
- Line bottom of prepared baking sheet with butter crackers. Top evenly with 3 1/2 cups of Cheddar cheese and bake until melted, about 5 minutes. Remove from oven.
- In a bowl, whisk together sour cream, mayonnaise, heavy cream, garlic powder, pepper, eggs, and remaining 3/4 teaspoon salt.
- Spread squash mixture over melted cheese, then pour egg mixture evenly over squash.
- Top with remaining 1 cup cheese. Mix crushed crackers with melted butter and sprinkle over the top.
- Bake until center is set, about 25 minutes. Let cool for 20 minutes before serving.
Notes