French Onion Green Bean Casserole
French Onion Green Bean Casserole combines fresh green beans, sweet caramelized onions, savory thyme sauce, melted Gruyère cheese, and crispy Parmesan breadcrumbs. A delicious homemade Thanksgiving side dish without canned soup!
Ingredients
- 4 large yellow onions, thinly sliced
- 8 tablespoons unsalted butter, divided (4 tablespoons for onions, 2 tablespoons for sauce, 2 tablespoons for topping)
- 3 tablespoons all-purpose flour
- ¼ cup dry white wine
- ½ tablespoon sherry vinegar, 1½ teaspoons
- 2 cups chicken stock
- 1 teaspoon fresh thyme, minced
- 1½ cups shredded Gruyère cheese
- 2 pounds fresh green beans, trimmed and cut into thirds
- 1½ teaspoons freshly ground black pepper, divided or to taste
- 1 cup panko breadcrumbs
- ¼ cup freshly grated Parmesan cheese
- Salt, to taste
Equipment
Instructions
- Caramelize onions: Melt 4 tablespoons butter in a large saucepan over medium-high heat. Add onions and cook 15 minutes, stirring frequently and covering between stirs. Reduce heat to medium and cook another 35–40 minutes until deeply golden. Season lightly with salt.
- Blanch beans: Bring a large pot of salted water to a boil. Add green beans and blanch for 3–4 minutes until crisp-tender. Drain well.
- Make sauce: Push onions to the sides of the pan. Melt remaining 2 tablespoons butter in the center, then stir in flour. Cook 2–4 minutes until bubbly. Mix into onions.
- Add thyme, white wine, sherry vinegar, and black pepper. Cook 2 minutes. Gradually stir in chicken stock and simmer 6–8 minutes until thickened. Season with salt.
- Make topping: Melt 2 tablespoons butter in a small skillet. Add panko and toast 3–5 minutes until golden. Cool slightly, then stir in Parmesan.
- Assemble: Preheat broiler. Toss green beans with onion sauce and transfer to a greased 9x13-inch broiler-safe baking dish.
- Sprinkle Gruyère over the casserole. Broil 2–3 minutes until melted and golden.
- Add toasted Parmesan breadcrumbs and broil about 30 seconds more, watching closely. Serve warm.
Notes
Sandy's Tips:
Make ahead: Prepare the onion sauce and green beans separately up to 2 days ahead. Refrigerate and assemble before serving.
Storage: Refrigerate leftovers up to 3–4 days.
Reheat: Warm covered at 350°F until heated through. Refresh the breadcrumbs if needed.
Cheese: Substitute Swiss or Comté for Gruyère.
No wine: Use additional chicken stock.
Vegetarian: Substitute vegetable stock.
Broiler tip: Watch closely to prevent burning.
Nutrition Facts
Calories: 372kcal, Carbohydrates: 31g, Protein: 15g, Fat: 22g, Saturated Fat: 13g, Polyunsaturated Fat: 1g, Monounsaturated Fat: 6g, Trans Fat: 0.5g, Cholesterol: 61mg, Sodium: 390mg, Potassium: 555mg, Fiber: 5g, Sugar: 14g, Vitamin A: 1409IU, Vitamin C: 22mg, Calcium: 385mg, Iron: 2mg