Four Onion Gratin

Indulge in the rich, savory flavors of Four Onion Gratin, a hearty side dish showcasing the depth and sweetness of four perfectly balanced onion varieties—yellow onions, red onions, leeks, and shallots. Gently sautéed in butter and simmered with garlic, fresh thyme, and creamy Gruyère cheese, this luxurious gratin is topped with a golden layer of crunchy breadcrumbs and Parmesan, adding irresistible texture and flavor. Perfect for family dinners or holiday gatherings, this baked dish is as comforting as it is elegant, making it a show-stopping complement to any main course. Ready in just over an hour, Four Onion Gratin brings a gourmet touch to your table without the fuss! Keywords: onion gratin recipe, cheesy onion side dish, elegant holiday side, baked gratin with breadcrumbs.

Nutriscore Rating: 55/100

Prep Time:20 mins

Cook Time:45 mins

Total Time:65 mins

Servings: 6

Ingredients

• 2 medium, thinly sliced Yellow onion
• 2 medium, thinly sliced Red onion
• 2 large, white and light green parts only, sliced Leek
• 4 medium, finely chopped Shallots
• 4 tablespoons Unsalted butter
• 3 cloves, minced Garlic
• 1.5 cups Heavy cream
• 1.5 cups, grated Gruyère cheese
• 0.5 cups, grated Parmesan cheese
• 2 teaspoons, chopped Fresh thyme
• 1 teaspoon Salt
• 0.5 teaspoon Black pepper
• 0.75 cups Breadcrumbs
• 1 tablespoon Olive oil

Directions

Step 1

Preheat the oven to 375°F (190°C). Grease a 2-quart baking dish with butter or cooking spray and set aside.

Step 2

In a large skillet, melt the butter over medium heat. Add the yellow onions, red onions, leeks, and shallots. Cook, stirring frequently, for 10-12 minutes until the onions are soft and translucent but not browned.

Step 3

Add the minced garlic to the skillet and cook for another 1-2 minutes, stirring, until fragrant.

Step 4

Pour in the heavy cream and mix well. Let it simmer gently for 3-4 minutes to thicken slightly.

Step 5

Take the skillet off the heat and stir in the thyme, salt, black pepper, and half of the Gruyère cheese. Combine until the cheese melts into the cream mixture.

Step 6

Transfer the onion and cream mixture to the prepared baking dish, spreading it out evenly.

Step 7

In a small bowl, mix the breadcrumbs, olive oil, Parmesan cheese, and the remaining Gruyère cheese. Sprinkle this mixture evenly over the top of the onions in the baking dish.

Step 8

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

Step 9

Remove the gratin from the oven and let it rest for 5 minutes to set before serving.

Step 10

Garnish with additional fresh thyme leaves if desired. Serve warm as a decadent side dish.

Nutrition Facts

Serving size	1654.1 grams (1654.1g)

Amount per serving	% Daily Value*
Calories	3594

Total Fat 272.60g	349%
Saturated Fat 151.40g	757%
Polyunsaturated Fat 7.10g
Cholesterol 751mg	250%
Sodium 5893mg	256%
Total Carbohydrate 175.40g	64%
Dietary Fiber 21.30g	76%
Total Sugars 49.30g
Protein 100.60g	201%

Vitamin D 48IU	238%
Calcium 2838mg	218%
Iron 13mg	71%
Potassium 1914mg	41%

*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: 69.0%

Protein: 11.3%

Carbs: 19.7%