Ingredients

32 ounces frozen cubed hash browns, thawed

¼ cup (½ stick / 57 g) unsalted butter, melted

2 cups (226 g) sharp cheddar cheese, shredded

1 ½ cups (345 g) sour cream

¼ cup (½ stick / 57 g) unsalted butter

1 small yellow onion, diced

2 teaspoons garlic, minced

¼ cup (31 g) all-purpose flour

1 teaspoon kosher salt

½ teaspoon black pepper

½ teaspoon cayenne pepper

½ teaspoon dried mustard

½ cup (120 g) chicken broth, room temperature

½ cup (122.5 g) whole milk, room temperature

2 large yellow onions, thinly sliced, layers separated (about 4 cups)

4 cups (32 ounces) vegetable oil

½ teaspoon kosher salt

Instructions

Step 1: Preheat your oven to 350°F (175°C) and spray a 9×13-inch baking dish with nonstick cooking spray.

Step 2: In a large bowl, combine the thawed hash browns, melted butter, shredded cheddar cheese, and sour cream. Mix well and set aside.

Step 3: To make the sauce, melt ¼ cup (½ stick) of butter in a medium non-stick skillet over medium heat.

Step 4: Add the diced small yellow onion and cook until softened, about 3–5 minutes. Add the minced garlic and cook for another minute.

Step 5: Stir in the flour, kosher salt, black pepper, cayenne pepper, and dried mustard. Cook for one more minute to remove the raw flour taste.

Step 6: Slowly whisk in the whole milk and chicken broth. Continue to cook, whisking constantly until the sauce thickens.

Step 7: Pour the sauce into the potato mixture and stir to combine thoroughly. Transfer everything into the prepared baking dish.

Step 8: Bake uncovered for 45–50 minutes, or until the casserole is bubbly and heated through.

Step 9: While the casserole bakes, prepare the fried onions. Line a large baking sheet with two layers of paper towels and set aside.

Step 10: Heat the vegetable oil in a large saucepan over medium-high heat to 350°F (175°C).

Step 11: Working in batches, fry about 1 cup of thinly sliced onions in the hot oil. Stir occasionally and cook until the onions turn pale golden brown, about 2–5 minutes.

Step 12: Use a fine mesh strainer or slotted spoon to transfer the onions onto the paper towels to drain excess oil. Sprinkle with ½ teaspoon kosher salt while still warm.

Step 13: Once the casserole is done baking, remove it from the oven and top with the crispy fried onions before serving.

Tips & Variations

For a vegetarian version, substitute the chicken broth with vegetable broth.

Use gruyère or a mix of cheddar and mozzarella for a richer cheese flavor.

Prepare the fried onions in advance and store them in an airtight container to save time.

To make it spicier, increase the cayenne pepper slightly or add some smoked paprika.

FAQs

Can I use fresh potatoes instead of frozen hash browns?

Yes, you can peel, cube, and parboil fresh potatoes before using them for this recipe. Make sure they are drained well to avoid excess moisture in the casserole.

How can I make the fried onions crispier?

Slice the onions thinly and fry them in hot oil without crowding the pan. Drain on paper towels immediately after frying and season while still warm. Using fresh oil and maintaining the proper oil temperature also helps achieve crispiness.