Onion Casserole

Indulge in the rich, savory goodness of this Onion Casserole, a comforting dish that transforms humble yellow onions into a show-stopping centerpiece. Featuring sweet caramelized onions layered with a velvety Gruyere-infused béchamel sauce, this recipe is topped with a crispy panko-Parmesan crust that adds the perfect crunch to every bite. Enhanced with aromatic garlic and fresh thyme, this casserole strikes a delectable balance between creamy and crispy textures. Ideal as a crowd-pleasing side dish or a vegetarian main course, this dish is easy to prepare with just 20 minutes of hands-on time. Perfect for holidays, potlucks, or cozy weeknight dinners, this Onion Casserole is sure to become a new family favorite.

Nutriscore Rating: 58/100

Prep Time:20 mins

Cook Time:50 mins

Total Time:70 mins

Servings: 6

Ingredients

• 6 medium Yellow onions
• 4 tablespoons Butter
• 2 tablespoons All-purpose flour
• 1.5 cups Whole milk
• 0.5 cups Heavy cream
• 1.5 cups Shredded Gruyere cheese
• 1 teaspoon Salt
• 0.5 teaspoons Ground black pepper
• 0.5 teaspoons Garlic powder
• 1 cup Panko breadcrumbs
• 0.5 cups Parmesan cheese, grated
• 2 tablespoons Olive oil
• 1 teaspoon Fresh thyme leaves

Directions

Step 1

Preheat your oven to 375°F (190°C). Grease a 9x9-inch casserole dish with butter or non-stick spray and set aside.

Step 2

Peel and slice the yellow onions into thin, even rings. Separate the rings to ensure even cooking.

Step 3

In a large skillet over medium heat, melt 3 tablespoons of butter. Add the sliced onions and sauté for 15-20 minutes, stirring occasionally, until the onions are soft and caramelized. Reduce heat if necessary to avoid burning.

Step 4

While the onions are caramelizing, prepare the béchamel sauce. In a medium saucepan, melt the remaining 1 tablespoon of butter over medium heat. Whisk in the flour and cook for 1-2 minutes, stirring constantly, to create a roux.

Step 5

Gradually whisk in the milk and heavy cream. Continue cooking, whisking frequently, until the mixture thickens into a smooth sauce, about 3-4 minutes. Remove from heat and stir in 1 cup of shredded Gruyere cheese, salt, pepper, and garlic powder until smooth. Set aside.

Step 6

Once the onions are caramelized, transfer them to the greased casserole dish. Pour the cheese sauce evenly over the onions, gently stirring to combine and coat the onions.

Step 7

In a small mixing bowl, combine the panko breadcrumbs, grated Parmesan cheese, olive oil, and fresh thyme leaves. Stir until the breadcrumbs are evenly coated with the oil.

Step 8

Sprinkle the breadcrumb mixture evenly over the onion and cheese mixture in the casserole dish.

Step 9

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

Step 10

Remove the casserole from the oven and allow it to cool for 5 minutes before serving. Enjoy as a side dish or main course!

Nutrition Facts

Serving size	1512.2 grams (1512.2g)

Amount per serving	% Daily Value*
Calories	2635

Total Fat 194.30g	249%
Saturated Fat 99.00g	495%
Polyunsaturated Fat 4.50g
Cholesterol 516mg	172%
Sodium 5078mg	221%
Total Carbohydrate 132.70g	48%
Dietary Fiber 14.10g	50%
Total Sugars 50.40g
Protein 92.70g	185%

Vitamin D 206IU	1030%
Calcium 2690mg	207%
Iron 6mg	33%
Potassium 1693mg	36%

*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: 66.0%

Protein: 14.0%

Carbs: 20.0%