Comforting Creamed Onion Casserole – So, you know how sometimes you just need comfort food that feels like a big hug? Let me introduce you to this Comforting Creamed Onion Casserole. Seriously, it’s like the underdog of casseroles—simple, humble, but absolutely irresistible. We’re talking soft, buttery onions in a creamy sauce topped with golden, crispy breadcrumbs. It’s one of those dishes that’s ridiculously easy to make but tastes like you put in way more effort than you actually did. Who doesn’t adore that?
The first time I made this casserole, I was in a mood—you know, one of those dreary days where you just need something comforting, quick, and foolproof. I looked around my kitchen, saw a bunch of onions, and thought, “Can I really make these the star of the show?” Well, turns out I could. Once that buttery, oniony goodness started filling the kitchen, my husband peeked in, suspicious at first. But by the time it was out of the oven, bubbly and golden, he was sold. Even my kids, who normally turn their noses up at anything remotely vegetable-like, couldn’t resist it. I swear, they were asking for seconds before I even sat down.
What makes this Comforting Creamed Onion Casserole truly special?
What makes this casserole super great? It’s the excellent harmony of delicate, caramelized onions and that decadent, creamy sauce that feels indulgent without being heavy. And then you’ve got the breadcrumbs on top—seriously, who doesn’t love a good crunchy topping? The nutmeg adds this subtle warmth that just takes it to another level. It’s fancy enough to impress at dinner but easy enough for a weeknight. Plus, you probably already keep most of the components in your pantry. Win-win, right?
What You Need To Make This Comforting Creamed Onion Casserole Recipe?
Onions: You’re going to want about five medium onions here. Yes, I know it seems like a lot, but trust me, they cook down into this soft, sweet, magical base. Don’t skimp on them—these guys are the star of the show. Slice them into half-rings so they cook evenly.
Butter: Seven tablespoons. Yep, you read that right! It’s what makes everything so rich and delicious. You’ll need some to sauté the onions and the rest to help get that golden, buttery breadcrumb topping. No regrets here!
Breadcrumbs: Speaking of breadcrumbs, one cup is all you need. You could use regular store-bought ones, but if you’ve got homemade, even better! They’ll give that perfect crunchy contrast to the creamy onions underneath.
All-Purpose Flour: Just three tablespoons. This is what thickens everything up and turns those sautéed onions into a creamy, dreamy casserole. It’s like the unsung hero of the dish.
Whole Milk: One and a quarter cups of whole milk—don’t try to get all fancy and use skim milk. We want richness, people! It brings that smooth, velvety texture that makes this casserole so irresistible.
Nutmeg: Just a pinch of nutmeg, 1/4 teaspoon to be exact. Sounds weird, I know, but it adds this warm, cozy vibe that makes the whole dish feel special. Don’t skip it!
Salt & Pepper: Half a teaspoon of salt and black pepper is all you need to season those onions and the sauce. Adjust to your taste, but definitely don’t forget to season at every step. You want all the flavors to come together perfectly.
Steps To Make Comforting Creamed Onion Casserole:
Alright, first things first—preheat that oven to 350°F. Grease up your casserole dish (an 8×8 or 9×5 works great), and set it on a cookie sheet just in case it gets a little bubbly in the oven.
Now, grab a large saucepan and melt 3 tablespoons of butter over medium heat. Toss in your onions and sauté them for about 5 minutes until they start to soften up and smell amazing.
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Next, add the water, salt, pepper, and that tiny pinch of nutmeg. Lower the heat, cover it up, and let those onions cook down for 15 to 18 minutes. If it starts to look a little dry, just add a splash of water to keep things moving.
While that’s happening, whisk the flour into the onion mixture, followed by the milk. Keep whisking until the sauce thickens up—about 2 to 3 minutes. Give it a taste and add more salt and pepper if needed.
Transfer everything to your prepared casserole dish. In a small bowl, mix the remaining 4 tablespoons of butter with the breadcrumbs and sprinkle that deliciousness on top of the onions.
Pop it into the oven and bake for 15 to 20 minutes until the top is bubbly and golden. Let it cool for a few minutes, then dig in!
Tip:
Here’s the thing with this Comforting Creamed Onion Casserole: the secret is in the onions. You want to give them time to really soften and caramelize, so don’t rush it. When you sauté them, get them to that perfect, golden stage where they’re starting to get sweet and tender. It’s not a fast process, but trust me, it’s worth every minute. Also, when you’re adding the flour, make sure to cook it out for a couple of minutes. You don’t want that raw flour taste sneaking into your casserole. And if you want that breadcrumb topping to be next-level? Toss your breadcrumbs with a little more melted butter before sprinkling them on top. It’ll make them extra crunchy and golden. No soggy breadcrumbs here!
Frequently Asked Questions:
Can I use a different type of milk?
Sure! Whole milk gives it that creamy richness, but if you’re in a pinch, you could try 2% milk. Just know that it won’t be as thick and luxurious. And if you’re going dairy-free, unsweetened almond or oat milk could work too—just adjust your expectations for creaminess!
How do I know when the casserole is done?
Good question! You’ll want the casserole to be bubbling around the edges and the breadcrumb topping to be golden brown. Usually, 15-20 minutes does the trick, but every oven is a little different. If it’s bubbling and golden, you’re good to go!
Can I make this casserole ahead of time?
Absolutely! You can prep the casserole and refrigerate it (minus the breadcrumb topping) for a day. When you’re ready to bake, just sprinkle the breadcrumbs on top and pop it in the oven. This makes it a great dish for holidays or busy nights when you want to get ahead.
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Planning to try this recipe soon? Pin it for a quick find later!
Comforting Creamed Onion Casserole
Ingredients
- 7 tbsp unsalted butter divided
- 5 medium onions sliced into half-rings
- 1 1/4 c water
- 1/2 tsp salt
- 1/2 tsp black pepper
- 1/4 tsp nutmeg
- 3 tbsp all-purpose flour
- 1 1/4 c whole milk
- 1 c breadcrumbs
Instructions
- Butter up a casserole dish (either 8x8 or 9x5) and place it on a cookie sheet—just a little insurance against any bubbling over—then set it aside.
- In a big pan, soften 3 tablespoons of butter over medium heat. Toss in your sliced onions and let them cook for around 5 minutes, stirring occasionally until they begin to soften.
- Next, add the water, salt, pepper, and a dash of nutmeg for that warm, cozy flavor. Turn the heat down to low, cover the pan, and let everything simmer for 15 to 18 minutes. If things start to look a bit dry, don’t hesitate to splash in a bit more water to keep it all saucy.
- While your onions are softening up, preheat your oven to 350°F.
- Once your onions are ready, sprinkle in the flour and slowly pour in the milk. Give it a good whisk until the mixture starts to thicken, which should only take a couple of minutes. If you think it needs more seasoning, go ahead and adjust the salt and pepper to taste.
- Pour that creamy onion mixture into your prepared casserole dish. Top it off with the remaining 4 tablespoons of butter, cut into bits, and an even layer of breadcrumbs.
- Pop it in the oven and bake for about 15 to 20 minutes, or until the top is bubbly and golden brown.
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!