I have to tell you EVERYTHING about this Southern Squash Casserole boos! It’s packed with onions, summer squash, zucchini, butter, eggs and sour cream then topped off with a bomb cracker crust. Just pure comfort food baby with its cheesy vibes. It’s a straight up hit.
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How to make Squash Casserole
Step 1: Cook the Veggies
- Add butter, olive oil, onion, squash, and zucchini to a nonstick skillet. Season with salt and black pepper.
- Cook over medium heat until the onions are translucent and the squash and zucchini are just barely still firm and start to caramelize. Stir frequently to evenly cook the vegetables.
Step 2: mix the veggies with the rest of the casserole ingredients
- Add sour cream, eggs, cayenne pepper, salt, and cheese to a medium bowl. Whisk everything together.
- Add in cooked vegetables.
- Gently stir the mixture with a spatula.
- Pour the casserole mixture into the prepared baking dish. Set aside.
Step 3: mix the cracker topping, top the casserole, and bake
- Add all cracker topping ingredients to a medium bowl.
- Whisk until you get small uneven streusel-like crumbs.
- Sprinkle the topping evenly over the vegetables.
- Bake until set, but the center just barely jiggles when touched. Remove from the oven, let it sit for a few minutes, and serve!
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Squash Casserole Recipe
Want to Save This Recipe, Boo?
Ingredients
For the Casserole:
- 2 tablespoons unsalted butter
- 1 tablespoon olive oil
- 1 medium yellow onion thinly sliced
- 1 pound yellow squash sliced (about 1/3 inch thick)
- 1 pound zucchini sliced (about 1/3 inch thick)
- 2 teaspoons kosher salt divided
- ½ teaspoon coarse ground black pepper
- 8 ounces sour cream
- 2 large eggs
- 1/8-1/4 teaspoon cayenne pepper depending on your heat preference
- 8 ounces shredded sharp cheddar
- ¼ cup grated Parmesan cheese
For the Cracker Topping:
- 3 tablespoons unsalted butter melted
- 1 sleeve Ritz crackers crushed
- ¼ cup grated Parmesan cheese
- 1 tablespoon minced fresh Italian parsley
Instructions
- Preheat oven to 350F. Set oven rack to middle position. Spray an 8×8 baking dish with nonstick cooking spray.
- In a 12-inch nonstick skillet, add butter, olive oil, onion, squash, and zucchini. Season with 1 ½ teaspoons salt and ½ teaspoon black pepper. Cook over medium heat until the onions are translucent and the squash and zucchini are just barely still firm and start to caramelize, about 8 minutes. Stir frequently to evenly cook the vegetables.
- Meanwhile, in a large bowl, whisk together sour cream, eggs, cayenne pepper, remaining ½ teaspoon salt, and cheese.
- Add in cooked vegetables and gently stir together with a spatula. Pour into prepared pan. Set aside.
- In a medium bowl mix all cracker topping ingredients until you get small uneven streusel-like crumbs. Evenly sprinkle topping over vegetables.
- Bake until set, but the center just barely jiggles when touched, about 35 minutes.
- Remove from the oven, let sit for about 5 minutes, and serve.
Notes
Nutrition
Recipe Tips
- Drain Your Veggies: Your zucchini and squash might give off a bit of water after sautéing them, so to avoid a soggy casserole, give them a quick drain in a colander. It’ll keep your casserole nice and creamy!
- Grate Your Own Cheese: For the smoothest melt, grate your own cheese. Freshly grated cheese doesn’t have the anti-caking agents that bagged cheese often has. Plus, it just tastes better!
- Perfectly Slice Your Squash: Slice your squash and zucchini just right! Too thin, and they might disintegrate during cooking – too thick, and you’ll end up with chunky, undercooked pieces. Aim for about 1/3 inch thickness, that’s the sweet spot.
- Let It Rest: Once you pull that golden beauty out of the oven, give it a few minutes to settle. This helps the casserole firm up a bit, making it easier to serve and ensuring it doesn’t fall apart on the plate.
Serving Suggestions
- A Lemon Roasted Chicken is just the ticket for slicing through that rich, creamy casserole. It’s light, it’s zesty, and it brightens up the whole plate. Or, for a true Southern touch, crispy Fried Chicken never fails!
- If I could eat pork every day with this yellow squash casserole, I would! Try some juicy Fried Pork Chops or go all out with Smothered Pork Chops drenched in rich gravy.
- A scoop of Southern Black-Eyed Peas or Butter Beans? Now THAT’s comfort food. They’re so creamy and earthy, and they just meld into the casserole vibes perfectly.
- Don’t forget the greens, y’all! A side of crisp Green Beans or a mix of steamed veggies can add some freshness to your hearty meal.
Recipe help
Can I make this casserole ahead of time?
Absolutely! Assemble it a day in advance without the crispy cracker topping, and keep it covered in the fridge. When you’re ready to bake, just sprinkle on the cracker mixture and pop it in the oven.
What cracker should I use for the topping?
I usually go for Ritz crackers because they’re soooo buttery and flaky, which makes for a delicious topping. However, feel free to experiment with any salty, crispy cracker you like. Even flavored crackers, why not?
Is there a dairy-free alternative for this recipe?
Sure thing, boo! For a dairy-free zucchini and squash casserole recipe, swap the butter with a plant-based alternative, use dairy-free cheese, and replace the sour cream with a non-dairy yogurt or sour cream substitute.
Can you Can you substitute frozen squash for fresh
You can, but it will be pretty watery – I would recommend thawing, in a colander to let the water drain and sprinkling with some salt to pull even more of the water out.
Yuuum anything with cheese and squash is exactly something I’d want to eat. This looks so simple too! Can’t wait to try it out, Thanks for the great recipe!
I love squash casserole. So delicious and yet nutritious too.
I made a gluten free version of this… just beautiful- thank you!!
You’re so welcome!
Never tried squash casserole before. looks so delicious. Thanks for sharing.
Awesome squash casserole! It’s so creamy and tasty! I even doubled the amount of sour cream and it was fantastic!
I made this tonight. The combination of squash, cheese sauce and crackers is the ultimate combo . My new favorite side dish!