Mom's Onion Casserole

Cozy comfort food doesn’t get much better than Mom's Onion Casserole, a timeless recipe brimming with layers of rich, savory flavor. This dish features beautifully caramelized yellow onions bathed in a creamy, homemade béchamel sauce, topped with gooey melted cheddar cheese and a golden, crunchy panko breadcrumb crust. Perfect for family gatherings, holiday spreads, or an indulgent weeknight side dish, this casserole is a tribute to simple ingredients transformed into something magical. With just a touch of garlic powder, a buttery crumb topping, and a sprinkle of fresh parsley for garnish, this baked delight is sure to warm hearts and appetites alike. Best of all, it’s easy to make in under an hour, making it a satisfying winner any time of year.

Nutriscore Rating: 60/100

Prep Time:15 mins

Cook Time:40 mins

Total Time:55 mins

Servings: 6

Ingredients

• 4 pieces large yellow onions
• 3 tablespoons unsalted butter
• 2 tablespoons all-purpose flour
• 1.5 cups whole milk
• 0.5 cups heavy cream
• 1 teaspoons salt
• 0.5 teaspoons black pepper
• 0.5 teaspoons garlic powder
• 1 cups grated cheddar cheese
• 0.5 cups panko breadcrumbs
• 1 tablespoon olive oil
• 2 tablespoons fresh parsley (optional, for garnish)

Directions

Step 1

Preheat your oven to 375°F (190°C).

Step 2

Peel the onions and slice them into thin rings.

Step 3

In a large skillet, melt the butter over medium heat. Add the onion slices and sauté for 10-12 minutes, stirring occasionally, until they become soft and translucent. Remove from heat.

Step 4

In a medium saucepan over medium heat, whisk together the flour and butter until a smooth paste forms. Slowly add the milk and heavy cream, whisking constantly to avoid lumps.

Step 5

Cook the milk mixture for 4-5 minutes, stirring often, until it thickens slightly. Season the mixture with salt, black pepper, and garlic powder.

Step 6

Grease a 9x9-inch casserole dish. Spread half the sautéed onions in the bottom of the dish.

Step 7

Pour half of the cream mixture over the onions. Add a layer of grated cheddar cheese.

Step 8

Repeat the layering: add the remaining onions, then pour over the rest of the cream mixture, and top with another layer of grated cheddar cheese.

Step 9

In a small bowl, combine the panko breadcrumbs with olive oil and mix until evenly coated. Sprinkle this mixture over the top of the casserole.

Step 10

Bake in the preheated oven for 25-30 minutes, or until the top is golden and bubbling.

Step 11

Remove the casserole from the oven and allow it to rest for 5 minutes before serving.

Step 12

Garnish with fresh parsley, if desired, and serve warm.

Nutrition Facts

Serving size	(1303.9g)

Amount per serving	% Daily Value*
Calories	1896.3

Total Fat 139.6g	0%
Saturated Fat 78.0g	0%
Polyunsaturated Fat 1.7g
Cholesterol 376.9mg	0%
Sodium 3460.8mg	0%
Total Carbohydrate 110.0g	0%
Dietary Fiber 12.2g	0%
Total Sugars 46.7g
Protein 52.6g	0%

Vitamin D 185.0IU	0%
Calcium 1428.3mg	0%
Iron 3.9mg	0%
Potassium 1662.5mg	0%

*The % Daily Value tells you how much a nutrient in a serving of food contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.

Source of Calories

Fat: 65.9%

Protein: 11.0%

Carbs: 23.1%