There’s something so nostalgic and comforting about a good hash brown casserole.
I’ve made this for family gatherings, lazy Sunday brunches, and even holiday dinners—and it never lasts long.
The creamy filling, cheesy goodness, and that irresistible crunch of homemade fried onions on top bring everyone back for seconds.
Why I Love This Recipe
It’s a guaranteed crowd-pleaser—creamy, cheesy, crispy all in one bite.
Easy to prep ahead and bake fresh when needed.
That homemade fried onion topping is a total flavor upgrade from the canned kind.
What You’ll Need (Ingredient Highlights)
Hash browns: Use thawed frozen cubed potatoes for convenience.
Sour cream & cheddar cheese: For a rich and creamy base.
Homemade sauce: Made with onions, garlic, milk, broth, and spices.
Fried onions: Thinly sliced and fried until golden brown and crispy.
Pro Tips Before You Start
Make sure your hash browns are fully thawed for even baking.
Don’t skip the cayenne and mustard powder—they add just the right kick.
Use a thermometer to keep your frying oil around 350°F for perfect onions.
How to Make Hash Brown Casserole with Fried Onions
Step 1: Prep the Oven and Dish
Preheat oven to 350°F (175°C).
Grease a 9×13-inch baking dish with nonstick spray.
Step 2: Mix the Potato Base
In a large bowl, combine thawed hash browns, melted butter, shredded cheddar cheese, and sour cream.
Mix well and set aside.
Step 3: Cook the Sauce
In a nonstick skillet, melt butter over medium heat.
Add diced onion and cook until soft.
Stir in garlic, then add flour, salt, pepper, cayenne, and mustard powder.
Cook for a minute.
Slowly whisk in milk and chicken broth until the sauce thickens.
Pour this into the potato mixture and stir to combine.
Transfer the mixture to the baking dish.
Step 4: Bake the Casserole
Bake uncovered for 45–50 minutes, or until bubbly and heated through.
Step 5: Fry the Onions
Heat vegetable oil to 350°F in a large saucepan.
Fry the sliced onions in batches, stirring occasionally, until golden brown.
Remove with a slotted spoon and drain on paper towels. Sprinkle with salt.
Step 6: Top and Serve
Once the casserole is baked, top with the crispy fried onions. Serve warm and enjoy!
What to Serve It With
Roast chicken or turkey
Scrambled eggs or an omelette
A fresh green salad with tangy vinaigrette
Variations / Substitutions
Swap sharp cheddar for Monterey Jack or pepper jack for a spicy kick.
Add chopped cooked bacon or ham to the potato mix.
Use Greek yogurt instead of sour cream for a lighter version.
Storage & Leftovers
Store in an airtight container in the fridge for up to 4 days.
Reheat in the oven at 350°F or in the microwave.
Fried onions are best freshly made, but leftovers can be crisped in the oven.
FAQs
Can I use fresh potatoes instead of frozen hash browns?
Yes, just peel, dice, and parboil them until slightly tender.
Can I make this dish ahead of time?
Absolutely! Assemble the casserole (without the onions), refrigerate, and bake fresh.
Do I have to fry the onions?
You can use store-bought crispy onions, but homemade is so worth it!
What’s the best cheese for this recipe?
Sharp cheddar gives the best flavor, but any melting cheese works.
Is this dish spicy?
Just a touch from cayenne—adjust to your taste.
Can I freeze leftovers?
Yes, though the texture of potatoes may change slightly upon reheating.
What’s the best way to reheat this?
Oven reheating helps keep the crispy texture.
Final Thoughts
If you’re looking for a side dish that disappears fast and brings rave reviews, this hash brown casserole with fried onions is it.
It’s indulgent, delicious, and perfect for any cozy gathering or weekend comfort meal.
Crispy Hash Brown Casserole
Ingredients
Potatoes:
- 32 ounces frozen cubed hash browns thawed
- ¼ cup 57 g unsalted butter, melted
- 2 cups 226 g sharp cheddar cheese, shredded
- 1½ cups 345 g sour cream
Sauce:
- ¼ cup 57 g unsalted butter
- 1 small yellow onion diced
- 2 tsp garlic minced
- ¼ cup 31 g all-purpose flour
- 1 tsp kosher salt
- ½ tsp black pepper
- ½ tsp cayenne pepper
- ½ tsp dried mustard
- ½ cup 120 g chicken broth
- ½ cup 122.5 g whole milk
Fried Onions:
- 2 large yellow onions thinly sliced (about 4 cups)
- 4 cups 32 oz vegetable oil
- ½ tsp kosher salt
Instructions
- Preheat oven to 350°F. Grease a 9×13-inch baking dish.
- In a bowl, mix hash browns, melted butter, cheese, and sour cream.
- For the sauce, melt butter in a skillet. Cook onions until soft.
- Add garlic, then flour and seasonings. Cook 1 minute.
- Slowly add milk and broth, whisk until thickened.
- Pour into potato mix. Stir and transfer to baking dish.
- See full steps with tips & photos → https://p4pd.org/crispy-hash-brown-casserole/
Notes
- Thaw hash browns thoroughly to avoid excess moisture.
- You can prep the base and fry onions ahead, then assemble before baking.
- Sub store-bought crispy onions if you're short on time.
