A classic Southern Sweet Onion Casserole featuring buttery Ritz crackers, creamy cheddar cheese, and sweet Vidalia onions—pure comfort food.
You know those recipes that instantly bring you back to your grandma’s kitchen? The ones that make the whole house smell like home? Well, this Southern Sweet Onion Casserole is exactly that. It’s creamy, cheesy, buttery, and layered with sweet Vidalia onions that practically melt in your mouth.
I remember the first time I had this at a family potluck. It was one of those late-spring Sundays—everyone milling around the backyard, mason jars of sweet tea in hand, and the unmistakable smell of something amazing wafting from the kitchen. Someone handed me a plate piled high with barbecue, slaw, and this golden, bubbly casserole. One bite, and I was hooked. The sweet onions, the gooey cheese, the crunchy topping—it was simple but perfect. I begged for the recipe before I left, and let me tell you, it’s been a staple ever since.
Why You’ll Love This Southern Sweet Onion Casserole Recipe?
- Vidalia Onions Are the Star: These naturally sweet onions caramelize as they cook, making them the perfect base for a savory casserole.
- Crunchy, Buttery Topping: Crumbled Ritz crackers mixed with melted butter create that irresistible golden crust.
- Simple Pantry Staples: You probably already have most of these ingredients on hand.
- Crowd-Pleaser: It’s hearty, cheesy, and hits that sweet-savory balance that makes everyone go back for seconds.
- Perfect for Any Occasion: Sunday dinners, potlucks, holidays—you name it.
Ingredient Notes:
The beauty of this dish? It’s simple. But each ingredient has its role in making this casserole unforgettable.
- Vidalia Onions: The sweet onion variety is key here. If you can’t find Vidalias, opt for any sweet onion. Yellow onions can work in a pinch but will have a sharper bite.
- Ritz Crackers: Buttery, flaky, and perfect for that crispy topping. If you want to get creative, try swapping with crushed saltines or even panko.
- Cheddar Cheese: Sharp cheddar balances the sweetness of the onions. Pre-shredded works fine, but if you have time, grate it fresh—it melts like a dream.
- Evaporated Milk: Adds creaminess without making the casserole too heavy. Regular milk can sub in if needed, but the texture won’t be quite as rich.
- Eggs: They help bind everything together, giving you those beautiful, cohesive slices.
- Butter: Because in Southern cooking, butter is basically its own food group.
How To Make Southern Sweet Onion Casserole?
Step 1. Prep Your Pan & Oven
Preheat your oven to 375°F. Give a 9×13-inch baking dish a good spray of nonstick cooking spray (because nobody wants stuck-on casserole when you’re scooping out that first bite).
Step 2. Soften the Onions
Slice your Vidalia onions into thin half-moons—about 1/4 inch thick. Place them in a saucepan and cover with water. Bring to a boil, then reduce the heat and let them simmer for 8 minutes until they’re soft but not mushy. Drain and immediately toss them with 2 tablespoons of butter while they’re still warm so it melts right in.
Step 3. Make the Filling
In a large bowl, whisk together 3 eggs and a 5 oz can of evaporated milk. This is going to make everything luxuriously creamy. Add the cooked onions, 1 cup of crushed Ritz crackers, 1 1/2 cups of grated cheddar cheese, 1 teaspoon of salt, and 1/4 teaspoon of pepper. Stir it all together until you’ve got a glorious, cheesy onion mixture.
Step 4. Assemble the Casserole
Pour the onion mixture into your prepared baking dish, spreading it out evenly.
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Step 5. Add the Buttery Topping
Mix 1 cup of crushed Ritz crackers with 3 tablespoons of melted butter. Sprinkle this golden goodness all over the top. It’s the kind of topping that gets all golden and crispy in the oven—drool.
Step 6. Bake Until Golden
Pop it in the oven and bake for 45 minutes, or until the center is set and the top is golden brown and bubbly. Let it cool for a few minutes before digging in (if you can wait that long).
Storage Options:
- Fridge: Store any leftovers in an airtight container in the fridge for up to 4 days.
- Reheat: Warm in the oven at 350°F until heated through, or zap individual portions in the microwave.
- Freezer-Friendly: Yep, you can freeze it! Wrap tightly and freeze for up to 3 months. Thaw overnight in the fridge before reheating.
Variations and Substitutions:
- Swap the Cheese: Gouda, mozzarella, or even pepper jack for a little kick.
- Add Protein: Stir in some crumbled bacon or shredded chicken for a heartier dish.
- Make It Gluten-Free: Use gluten-free crackers instead of Ritz.
- Turn Up the Heat: Add a dash of cayenne or red pepper flakes if you like a little spice.
- Herb It Up: A sprinkle of fresh thyme or parsley can give it a fresh, earthy note.
What to Serve with Southern Sweet Onion Casserole?
This casserole shines as a side dish, but it plays well with a ton of mains.
- BBQ Pulled Pork: The sweetness of the onions cuts through the smoky richness.
- Fried Chicken: A classic Southern pairing—crispy chicken + cheesy casserole? Yes, please.
- Grilled Steak: The buttery onions balance out a juicy steak perfectly.
- Fresh Green Salad: For a little crunch and balance.
- Cornbread: Because carbs on carbs is sometimes the right choice.
Frequently Asked Questions:
Can I make this casserole ahead of time?
Absolutely! Assemble it the night before, cover, and refrigerate. Just bake it fresh when you’re ready to serve.
Can I use regular onions instead of Vidalia?
You can, but the flavor will be a bit sharper. If you go with yellow onions, sauté them first to mellow out the bite.
Can I make this vegetarian?
It already is! But if you want to amp up the veggies, try adding sautéed mushrooms or spinach.
And there you have it—Southern Sweet Onion Casserole in all its golden, bubbly glory. It’s sweet, cheesy, crunchy, and straight-up comforting. The kind of dish that disappears from the potluck table in minutes.
So go ahead, make it, and let me know what you think. I bet you’ll be adding it to your recipe box before you even finish that first slice.
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Southern Sweet Onion Casserole
Ingredients
For the Casserole:
- 4 large Vidalia onions halved and sliced into 1/4-inch thick slices
- 2 tablespoons unsalted butter
- 3 large eggs
- 1 5 oz can evaporated milk
- 1 cup Ritz crackers finely crumbled
- 1 1/2 cups sharp cheddar cheese grated
- 1 teaspoon salt
- 1/4 teaspoon ground black pepper
For the Topping:
- 1 cup Ritz crackers finely crumbled
- 3 tablespoons unsalted butter melted
Instructions
Preheat and Prepare:
- Preheat the oven to 375°F (190°C). Grease a 9x13-inch baking dish with nonstick spray or lightly coat with butter.
Soften the Onions:
- Place the sliced Vidalia onions in a medium saucepan and add enough water to cover them. Bring the water to a boil, then reduce the heat and simmer for 8 minutes, or until the onions are tender. Drain the onions thoroughly and toss them with 2 tablespoons of unsalted butter while still warm.
Prepare the Filling:
- In a large mixing bowl, whisk together 3 eggs and 5 oz of evaporated milk until well combined. Add the cooked onions, 1 cup of crumbled Ritz crackers, 1 1/2 cups grated cheddar cheese, 1 teaspoon salt, and 1/4 teaspoon black pepper. Stir until all ingredients are evenly incorporated.
Assemble the Casserole:
- Transfer the onion mixture to the prepared baking dish, spreading it evenly.
Make the Topping:
- In a small bowl, combine 1 cup of crumbled Ritz crackers with 3 tablespoons of melted butter. Mix well until the crumbs are coated. Sprinkle the topping evenly over the casserole.
Bake:
- Bake the casserole in the preheated oven for 45 minutes, or until the center is set and the top is golden brown. Allow the casserole to cool slightly before serving.
Notes
I’m Bitty, owner of nodashofgluten.com, where I share simple, delicious recipes for all tastes, including gluten-free. Check out my “About Me” page for more info!
