Baked mushroom rice casserole is just 5 ingredients and about 10 minutes to prep, but bakes up so tender, creamy, rich and delicious. This side dish is sure to impress!

Today's recipe for baked mushroom rice casserole is one I've loved since I was a kid.
I remember the first time my mom made it. It was just the two of us; I guess my dad and brother were gone that night.
And I was expecting not to enjoy it. At all. (We were unhelpful that way whenever she tried making a new dish.)
But I took one bite and changed my tune immediately.
This mushroom rice casserole is creamy, rich, savory and so delicious.
The rice, onions and mushrooms are so tender and they soak up the beef broth as they cook, giving these simple ingredients so much oomph.
I was surprised at the time by how much I loved it. Maybe that was the beginning of my love of onions and mushrooms, cause I adore both nowadays.

And it became a side dish I requested on the regular. "Mom, can you make that mushroom rice casserole thingy I love?"
And now as the mom, I love that this recipe is just 5 ingredients and only takes 10 minutes to prep. It's so quick and easy to throw together.
(Granted, it bakes for an hour, so you do need to be sure to plan accordingly for that.)
But it comes out with fluffy rice, tender veggies and a buttery, savory flavor that's hard to beat!
OK, let's get cooking so you can enjoy this dish, too!



Ingredient Notes:
Butter: Unsalted is the only kind I tend to have on hand, but you could substitute salted if that's what you use.
White rice: Regular long-grain white rice is perfect here. And while I am normally a brown rice only kind of gal, you just can't substitute it here; it'll never cook through.
Beef broth: The beef broth adds the savory richness to this dish, so I don't recommend substituting chicken or vegetable broth. Also, it's a lot of liquid, more than you would use stove-top because we're baking this uncovered in the oven.
Mushrooms: You can find a 6 oz. jar of mushrooms in liquid at most grocery stores. (Green Giant makes this and is what I use, but any brand will do.) Don't drain them! We're using the liquid from the jar, too.
You'll notice there's no salt or pepper listed in the recipe.
The sodium from the beef broth is plenty to season this casserole dish. But of course, as with anything, add some salt and pepper to taste at the table for your portion to get it to your liking.


We often have this mushroom rice casserole with some sort of red meat, such as steaks, or with pork chops or pork tenderloin.
It's a great pairing for hearty meats and comforting main dishes. And it would make an easy but impressive dish to serve friends and family.
Then you just need to add a side salad or a steamed or roasted veggie and dinner is done!
I hope you give this a try, whether it's a throw-back recipe for you as well or a brand new one you're looking to try.
Enjoy!
XO,
Kathryn
Baked Mushroom Rice Casserole
Ingredients
- 4 tablespoons unsalted butter
- 1 large onion, chopped
- 1 ½ cups white rice
- 2 (15 oz) cans beef broth
- 1 (6 oz) jar mushrooms, undrained
Instructions
- Preheat oven to 350.
- Melt butter in a large skillet. Add the onion and cook on medium heat until tender, about 5-6 minutes. Add the rice and stir in until well coated. Turn off the heat.
- Add the beef broth and mushrooms, with their liquid, and stir well. (If your pan isn't big enough, combine everything in a large bowl instead.)
- Transfer the rice mixture to a 9x13 casserole dish. Bake at 350 for 1 hour.







Bryan says
Maybe I missed it but it might be worth adding that the reason you need so much liquid is because it’s not covered vs on the stove it is covered.
Kathryn Doherty says
Thanks Bryan, that's a good note to point out!