My yellow squash casserole bakes up creamy and sliceable (never watery!) because the squash gets cooked down and pressed dry before anything else goes in. Sharp cheddar, Parmesan, and sour cream hold it together under a buttery cracker top, and I assemble it a day ahead whenever I’m hosting.
An old fashioned squash casserole with a cracker top
I first ate a squash casserole in New Orleans, where the local version is actually made with chayote, and it has been a fixture at my uncle’s table since his family moved to Atlanta a few years ago. I make this version once the garden gives me more yellow squash than I can give away.
Yellow squash is mostly water, and if it goes into the dish raw, that water ends up in the bottom of the pan. So I cook it down with the onion first, then press it in a colander until it stops dripping. It took me more than one batch to trust how hard to press. Press until the pile looks too dry and it will still bake up creamy. Eggs and sour cream set it into a soft custard, and Parmesan gives the cheddar something sharper to lean on.
It holds in the fridge assembled for a day, so it lands on my table at Thanksgiving as often as at a summer potluck.
P.S., This is also my answer to the question I get most on my squash casserole with stuffing: can I make it without the stuffing mix? Why yes, you can!
What goes into a squash casserole with Ritz crackers on top
Full ingredient list and detailed instructions in the recipe card.
- Pick small to medium yellow squash, about six for two pounds. The big late-summer ones carry more seeds and more water, so if that is what you have, scoop out the seedy core before slicing.
- Sour cream and two eggs set the filling into a soft custard. This is a squash casserole with sour cream rather than mayonnaise or canned soup, so it tastes like squash and cheese.
- Sharp cheddar carries the flavor and Parmesan sharpens it. Mild cheddar disappears here, so buy the sharpest block you can find and shred it yourself; pre-shredded cheese is coated in starch and melts stiffer.
- Buttery round crackers (Ritz or the store brand) crushed and tossed in melted butter make the top. Crush them by hand inside the sleeve so you get crumbs and small shards; the shards stay crunchy after baking.
Shruthi’s Top Tips
Getting a cheesy squash casserole to set instead of slump
- Cook the squash and onion until fully soft and the pan looks wet, then drain and press. Undercooked squash keeps releasing water in the oven and no amount of cheese hides that.
- Let the drained squash cool a few minutes before the eggs go in. Straight from the skillet it is hot enough to scramble them, and you get flecks of cooked egg instead of a smooth custard.
- Pull it when the center has a slight wobble and a knife in the middle comes out mostly clean. Give it the full 10 minute rest. It slices cleanly after that and falls apart before.
- To make it ahead, assemble everything except the cracker topping, cover, and refrigerate up to a day. Add the buttered crackers right before baking and add about 5 minutes. Crackers that sit on the wet filling overnight go soft.
- Doubling for a crowd, use two 9×13 dishes rather than one deeper one, or the center never sets before the top browns.
How to make yellow squash casserole
- Cook the sliced squash and onion in butter over medium heat until soft and the pan is wet, 10 to 12 minutes. Drain in a colander and press out as much liquid as you can.
- Return the squash to the skillet with the garlic, salt, and pepper for 1 minute, then let it cool a few minutes.
- Stir in the eggs, sour cream, most of the cheddar, and the Parmesan.
- Spread into a greased 9×13 dish, top with the remaining cheddar, then scatter the crackers tossed in melted butter over the top.
- Bake at 350F on the middle rack until golden and set with a slight wobble in the center, 30 to 35 minutes. Rest 10 minutes before serving.
How to serve yellow squash casserole
This is a side, so build the plate around it. At Thanksgiving it sits next to my green bean casserole with cream cheese and whatever is holding the center of the table. In summer it goes next to corn casserole with fresh summer corn, sliced tomatoes, and a bean salad. The eggs and cheese carry enough weight that a scoop beside a lentil loaf or a pot of beans makes a full vegetarian plate.
For a mixed table this is the dish everyone eats. Roast chicken thighs or a spiral ham alongside for the meat eaters and nobody needs a separate version. Kids go for the cracker top first, so I scatter a little extra over their corner. If you are planning the rest of the menu, my vegetarian Thanksgiving recipes cover the mains and desserts, and the savory sweet potato casserole is the other make-ahead side I lean on.
Variations
- Swap half the yellow squash for zucchini and you are close to my zucchini and squash casserole, which uses a different binder.
- Stir a cup of fresh or thawed corn kernels in with the cheese for a sweeter summer squash casserole.
- Use gluten-free buttery crackers and the dish is gluten-free; the topping works the same.
- For heat, a pinch of cayenne in the filling, or hot sauce at the table so the kids’ portions stay mild.
Storage and reheating
Leftovers keep covered in the fridge for 4 days. Reheat portions in a 350F oven or toaster oven for about 15 minutes so the top crisps again; the microwave works but the crackers go soft. I don’t freeze this one. The squash weeps as it thaws and the custard turns grainy.
Yellow Squash Casserole
Ingredients
- 3 tablespoons unsalted butter, divided
- 2 lbs yellow squash (about 6 medium), sliced into ¼-inch rounds
- 1 medium yellow onion, diced
- 2 cloves garlic, minced
- ¾ teaspoon kosher salt
- ¼ teaspoon ground black pepper
- 2 large eggs, beaten
- ½ cup sour cream
- 1½ cups shredded sharp cheddar cheese, divided
- ½ cup grated Parmesan
- 1½ cups crushed buttery round crackers (about 1 sleeve Ritz)
Instructions
- Preheat the oven to 350F with a rack in the middle. Grease a 9×13-inch baking dish.
- Melt 1 tablespoon of the butter in a large skillet over medium heat. Add the squash and onion and cook, stirring now and then, until soft and the pan looks wet, 10 to 12 minutes. Tip into a colander and press firmly with a spoon to squeeze out as much liquid as possible.
- Return the squash and onion to the skillet, add the garlic, salt, and pepper, and cook 1 minute. Let cool 5 minutes so the eggs don’t scramble.
- Stir in the eggs, sour cream, 1 cup of the cheddar, and the Parmesan. Spread into the baking dish and top with the remaining ½ cup cheddar.
- Melt the remaining 2 tablespoons butter, toss with the crushed crackers, and scatter over the top.
- Bake until the top is golden and the center is set with a slight wobble, 30 to 35 minutes. A knife in the middle should come out mostly clean. Rest 10 minutes before serving.
Notes
- Press the drained squash until it looks too dry; it bakes up creamy anyway, and skipping this makes the casserole soupy.
- Let the squash cool a few minutes before stirring in the eggs so they don’t scramble.
- To make ahead, assemble without the cracker topping, cover, and refrigerate up to 1 day; top with the buttered crackers just before baking and add about 5 minutes.
- Use gluten-free buttery crackers for a gluten-free casserole.
- Store leftovers covered in the fridge up to 4 days and reheat in a 350F oven about 15 minutes to re-crisp the top. Freezing is not recommended.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
