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This single serving Mushroom Casserole is rich, flavorful, and easy to make. Tender mushrooms and garlic are simmered in a homemade cream sauce, then baked with rice until tender. It’s a simple, satisfying meal that’s perfectly portioned for one.

Featured Comment
“Absolutely wonderful. Highly recommend it.”
– dragnlaw
Why You’ll Love This Recipe
- Made from scratch: No canned soup in this small mushroom casserole recipe, just fresh ingredients.
- Doubles well: Easily make a larger batch for two servings.
- Rich, savory flavor: Plenty of mushrooms, garlic and a rich sauce make every bite delicious.
There’s something so comforting about a warm, creamy casserole, and this small mushroom casserole with rice is one of my favorites. It’s simple to make, packed with flavor, and perfect for a satisfying meal. I love how the rice soaks up the rich, garlicky sauce, making every bite delicious. This dish is an easy way to enjoy a homemade, hearty meal without a lot of fuss.
This simple mushroom casserole is filling on its own but also works well as a side dish with baked chicken thighs, sautéed green beans or roasted carrots and a small loaf of French bread.

Ingredients

If you have leftover ingredients from this mini mushroom casserole recipe, check out our Leftover Ingredients Recipe Finder.
- Mushrooms: Use sliced cremini (baby bella) or white button mushrooms for their earthy flavor. To clean mushrooms, briefly rinse them in a colander under running water and pat them dry with a paper towel before cooking – don’t soak them, as they absorb water. Extra mushrooms can be used in small crustless spinach and mushroom quiche, chicken masala for one , mushroom pasta for one, or single serving beef stroganoff.
- Chicken Broth: Use low sodium chicken broth, or swap with vegetable broth for a vegetarian option. Leftover broth works well in our single serving soup recipes, chicken and dumplings for one or a single serving of risotto.
- Sour Cream: Adds creaminess; Greek yogurt is a good alternative. Leftovers can be used in butter chicken for one, a small Mexican street corn salad, or a mini German chocolate cake.
- Heavy Cream: Provides richness. Whole milk or half-and-half work but make the sauce thinner. Use extra cream in fettuccine Alfredo for one, mini hashbrown casserole, a small no-bake cheesecake.
- Rice: Medium or long-grain white rice or basmati work best. Brown rice needs more liquid and time. Leftover rice can be used in rice pudding for one.
See recipe card below for a full list of ingredients and measurements.
Recipe Variations
Customize your mushroom casserole with these simple changes:
- Cheesy Addition: Stir in shredded cheddar, Gruyère, or Parmesan before baking for extra flavor.
- Crispy Topping: After baking, remove the foil and sprinkle homemade breadcrumbs or crushed Ritz crackers mixed with melted butter over the top. Bake for another 5 minutes for a golden, crunchy finish.
- Add Vegetables: Stir in ¼ cup of steamed or blanched chopped broccoli before adding the cream mixture to the baking dish.
- Make It Heartier: Mix in cooked chicken, turkey, or tofu for added protein.
- Dairy-Free Option: Swap heavy cream for coconut cream, sour cream for a plant-based alternative, and use vegetable broth instead of chicken broth.
How To Make A Small Mushroom Casserole
These photos and instructions help you visualize how to make a small mushroom casserole. See the recipe box below for ingredient amounts and full recipe instructions.
- Preheat the oven to 375°F (190°C).

- Heat olive oil in a 10-inch skillet over medium heat. Add the onions and cook for about 2 minutes, stirring frequently, until translucent. Add the garlic and cook for 30 seconds.

- Increase the heat to medium-high and add a little more olive oil. Add the mushrooms, salt, and pepper. Cook for 5-7 minutes, stirring occasionally.

- Pour in the chicken broth and bring to a simmer.

- Remove the pan from the heat and stir in the sour cream, heavy cream, salt, and dried rosemary.

- Pour the uncooked rice into a 4×6-inch or a 5×5-inch baking dish.

- Pour the mushroom sauce over the rice and stir gently. Place the dish on a rimmed baking sheet to catch any spills.
- Cover tightly with foil and bake for 40 minutes. Remove the foil and check for excess liquid. If needed, bake uncovered for a few more minutes until the liquid has evaporated.

Expert Tips
- Read through the recipe first. This casserole comes together quickly, so review the steps and ingredient notes before starting.
- Adjust seasoning as needed. Depending on how salty your broth is, you may need to add more salt when serving.
- Skip Instant Rice. This recipe won’t work with Minute Rice or other quick-cooking varieties.

Frequently Asked Questions
Store in an airtight container in the refrigerator for up to 3 days. Reheat in the microwave or oven until warmed through.
Yes! Double the ingredients and use either two 5×5 inch baking dishes or use one 6×8 inch baking dish.
Ways To Use Leftover Ingredients
If you have any ingredients leftover from this recipe, check out our Leftover Ingredients Recipe Finder or you might like to consider using them in any of these single serving and small batch recipes:
If you’ve tried this small mushroom casserole recipe or any recipe on One Dish Kitchen please let me know how you liked it by rating the recipe and telling me about it in the comment section below.
If you take a picture please tag us on Instagram (@onedishkitchen) we’d love to see it!
Mushroom Casserole For One

Equipment
- 5-inch baking dish or use a 4×6-inch baking dish
Ingredients
- 1 ½ tablespoons olive oil -divided
- ¼ cup chopped onions
- 1 clove garlic -minced
- 4 ounces sliced mushrooms (1 cup)
- ½ teaspoon kosher salt -divided
- ⅛ teaspoon black pepper
- ⅓ cup low sodium chicken broth
- 3 tablespoons heavy cream
- 2 tablespoons sour cream
- ¼ teaspoon dried rosemary
- ¼ cup long-grain white rice
Instructions
- Preheat the oven to 375°F (190°C).
- Heat 1 tablespoon olive oil in a medium skillet over medium heat. Add the onions and cook for 2 minutes, stirring frequently until translucent. Add the garlic and cook for 30 seconds.
- Increase the heat to medium-high and add ½ tablespoon olive oil. Add the mushrooms, ¼ teaspoon salt, and pepper. Cook for 5 to 7 minutes, stirring occasionally.
- Pour in the chicken broth and bring to a simmer.
- Remove from heat and stir in the heavy cream, sour cream, ¼ teaspoon salt, and dried rosemary.
- Add the uncooked rice to a 4×6-inch or 5×5-inch baking dish.
- Pour the mushroom sauce over the rice and stir gently. Place the dish on a rimmed baking sheet.
- Cover tightly with foil and bake for 40 minutes. Serve hot.
Notes
- Read through the recipe first. This dish comes together quickly, so review the steps and ingredient notes before starting.
- Adjust seasoning as needed. Depending on how salty your broth is, you may need to add more salt when serving.
- Skip Instant Rice. This recipe won’t work with Minute Rice or other quick-cooking varieties.
Nutrition
The information shown is an estimate provided by an online nutrition calculator. It should not be considered a substitute for a professional nutritionist’s advice.


















Picked up some mixed mushrooms on sale, so I had to try this recipe. I also had farro so I used that instead of rice. The seasoning was spot on. Will be making again.
I’m so happy you enjoyed it!