Cheesy Onion Casserole

Thanks for sharing!

Sweet onions are the star of the show with this cheesy onion casserole. As the onions bake, they get soft and mild, making them the perfect base for herbs, cheese, and a buttery cracker topping.

This tasty onion casserole is a perfect side dish for holidays, Sunday suppers, and more. The oven brings 9 simple ingredients together in the most wonderful way.

This one just might even win over non-onion lovers. Because if ever there was a way to win someone over, cheese and a crumb topping are likely involved.

I am always on the hunt for fun new side dish recipes. For whatever reason, coming up with fun sides is the hardest part of meal planning for me.

It is too easy to get into a run with veggies. We tend to keep them simple, but that gets boring after a while.

So armed with a couple of giant sweet onions, it seemed like a good time to turn them into a casserole. After all, cheesy cabbage casserole has won over a cabbage hater or two. Why couldn’t we come up with something that could do the same for onions.

I looked online for a recipe that would do the trick, but I didn’t find what I was looking for. So, I developed this one instead.

Why You’ll Love This Casserole

As the name suggests, sweet onions are usually on the milder side to start with. However, cooking them down makes them even more mild and delicious.

There is no onion bite in this recipe. So even folks who don’t think they like onions may just become fans.

A lot of onion casserole recipes require you to sauté the onions for a while first. This recipe lets the oven do the work so there are fewer dishes and less active cooking time.

Some garlic salt, mustard powder, thyme, and paprika add some depth of flavor to the dish. The butter and cheese bring that rich goodness and keep the onions tender and delicious.

I used a mix of gruyere and smoked gouda in the casserole. They both have good flavor but aren’t too sharp.

That allows the onions to really shine through. However, you can use whatever good melting cheeses you like.

I am sure cheddar would be delicious. Monterey jack, Swiss, or provolone would all be tasty options as well.

Covering the casserole dish with foil and allowing the onions and cheese to have a nice long trip to the oven gives the onions a chance to soften nicely. It takes some time, but no actual effort once it is in the oven.

Once the onions are tender, it’s time to add the topping. Because after all, what is a casserole without some sort of crunchy topper?

Here, we opted to use some buttered cracker crumbs. We love cornflake topped casseroles, but the buttery texture of Ritz crackers seemed like a better option for this particular recipe.

Bake it a little bit longer to toast the cracker crumbs and finish it off, and it is time to dig in. Be prepared to fall in love after the first bite!

Tips and Tricks

This recipe works well in a 9×13-inch pan. You could make half of the recipe in an 8-inch square.

For a more rustic presentation, make the casserole in a 12-inch cast iron skillet.

Don’t worry if the pan looks really full when you put the onions in. They will shrink down as they cook.

I like the look of leaving the onions in rings. However, you can rough chop them or julienne them if you prefer.

This casserole goes great with turkey, ham, or roast beef. It is also great with grilled entrees. We loved it with BBQ pork chops and cowboy salad.

More Great Cheesy Side Dish Casseroles

Cheese and crackers also star in fresh pineapple casserole. It’s a sweet and salty side dish that sounds strange but tastes amazing.

Of course, it is hard to go wrong with funeral potatoes. A pan or two of those cheesy potatoes make an appearance at almost every holiday meal.

Corn casserole with cheese and green chiles is another wonderful option. It adds a little bit of spice to one of our all-time favorite sides.

For more inspiration, check out my collection of side dish recipes. There is sure to be something there you’ll love.

Thanks for sharing!