Caramelized Onion and Green Bean Gratin
Caramelized Onion and Green Bean Gratin pairs tender-crisp beans with deeply sweet onions and a creamy, gently spiced sauce. A Gruyère-Parmesan topping and buttery panko bake into a golden crust that adds satisfying crunch and nutty richness. Serve it alongside roast meats or as a standout holiday side when you want comfort and elegance in one dish.
- Prep45 mins
- Cook45 mins
- Serves10
- DifficultyMedium
- 1
Gather the ingredients.
- 2
Preheat the oven to 375 degrees F (190 degrees C).
- 3
Grease a 9x13-inch casserole dish.
- 4
Heat 2 tablespoons of butter in a large skillet over medium heat.
- 5
Add the onions to the pan; cook and stir until very soft and golden brown, about 15 minutes.
- 6
Stir in the sherry vinegar, then transfer the mixture to a small bowl and set aside.
- 7
In the same skillet, melt 2 more tablespoons of butter.
- 8
Whisk in 2 tablespoons of flour.
- 9
Cook over medium heat, stirring constantly, until the flour smells like baked pie crust, about 3 minutes.
- 10
Slowly whisk in the milk, about 1/2 cup at a time, then whisk in the nutmeg, cayenne pepper, and thyme.
- 11
Bring to a simmer and cook, whisking constantly, until thickened, 3 more minutes.
- 12
Transfer to a bowl and set aside.
- 13
Melt the remaining 2 tablespoons of butter in a clean skillet; stir in the panko until all the crumbs are coated; set aside.
- 14
Bring a large saucepan of salted water to a boil over medium heat, and boil the beans until bright green and crisp but not raw tasting, 3 to 4 minutes.
- 15
Drain very well.
- 16
Spoon half of the caramelized onions into the prepared casserole dish; top with the green beans.
- 17
Season with salt and black pepper.
- 18
Spread the reserved white sauce over the green beans; sprinkle with half of the Gruyere cheese.
- 19
Top with the rest of the onions, and use the back of a spoon to press the onions down into the sauce and cheese.
- 20
Top with the buttered panko crumbs, the remaining Gruyere, and the Parmesan cheese.
- 21
Bake in the preheated oven until hot throughout and lightly browned, about 30 minutes.
- 22
Let sit for 10 minutes before serving.
- 23
Serve and enjoy.
- Calories 201.03 kcal Moderate
- Protein 9.67 g Moderate
- Carbs 22.61 g Moderate
- Total Fat 8.1 g Moderate
- Saturated Fat 4.44 g High
- Trans Fat 0.0 g Low Source
- Cholesterol 21.12 mg Moderate
- Sodium 161.18 mg Moderate
- Fiber 3.58 g Moderate
- Sugar 6.93 g Moderate
- Added Sugar 0.0 g Low Source
- Calcium 259.58 mg Moderate
- Iron 0.9 mg Low Source
- Potassium 403.22 mg Low Source
- Vitamin A 70.86 mcg_rae Low Source
- Vitamin C 11.08 mg Moderate
- Vitamin D 0.78 mcg Low Source
Values are per serving. Percent Daily Values are based on a 2,000-calorie diet.
- Milk 🥛
- Wheat 🌾
- Gluten
- Onions 🧅
- Alcohol 🚫🍷
About This Recipe
Caramelized Onion and Green Bean Gratin is a French side dish recipe made with 13 ingredients. It takes about 1 hr 30 mins, serves 10, and is rated medium. Key ingredients include All Purpose Flour, Butter, Cayenne Pepper, and Grated Parmesan Cheese. Each serving provides about 201.03 kcal.
Recipe Questions
- What is Caramelized Onion and Green Bean Gratin?
- It is a French gratin recipe made with 13 ingredients, usually served for side dish.
- What is Caramelized Onion and Green Bean Gratin made of?
- The main ingredients are All-Purpose Flour, Butter, Cayenne Pepper, Grated Parmesan Cheese, Green Beans. The full list of 13 is above.
- How long does it take to make Caramelized Onion and Green Bean Gratin?
- About 1 hr 30 mins in total: 45 mins to prepare and 45 mins to cook.
- How many calories are in one serving?
- One serving provides about 201.03 kcal. The full nutrition breakdown is above.
- Is Caramelized Onion and Green Bean Gratin easy to make?
- This recipe is rated medium, with 13 ingredients and 23 steps.
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