This delicious julia child zucchini gratin is a creamy and comforting dish featuring tender zucchini and caramelized onions, topped with a crispy layer of Gruyère cheese. It’s a quick and easy meal that utilizes common pantry ingredients, offering flexibility for various substitutions. The rich, cheesy crust adds an irresistible texture to this classic recipe.
Ingredients Needed
- 6 tbsp (¾ stick) unsalted butter, plus extra for topping
- 1 lb yellow onions, halved and sliced (about 3 large onions)
- 2 lbs zucchini, sliced ¼-inch thick (about 4 zucchini)
- 2 tsp kosher salt
- 1 tsp freshly ground black pepper
- ¼ tsp ground nutmeg
- 2 tbsp all-purpose flour
- 1 cup hot milk
- ¾ cup fresh bread crumbs
- ¾ cup grated Gruyère cheese
How To Make Zucchini Gratin
- Preheat: Preheat the oven to 400°F.
- Cook the onions: Melt the butter in a large (12-inch) sauté pan over low heat. Add the onions and cook for about 20 minutes, stirring occasionally, until tender but not browned.
- Add the zucchini: Stir in the zucchini, cover, and cook for 10 minutes, until softened. Uncover, add salt, pepper, and nutmeg, then cook for another 5 minutes.
- Make the sauce: Sprinkle the flour over the mixture, stirring well. Pour in the hot milk and cook on low heat, stirring, until a thick sauce forms.
- Assemble the gratin: Transfer the mixture to an 8×10-inch baking dish. In a small bowl, combine the bread crumbs and Gruyère cheese, then sprinkle over the top. Dot with 1 tablespoon of butter, cut into small pieces.
- Bake: Bake for 20 minutes, until the top is golden brown and bubbly. Serve hot and enjoy!

Recipe Tips
- Drain Excess Moisture: After cooking the zucchini, ensure you drain any excess liquid to prevent the gratin from becoming watery.
- Use Fresh Nutmeg: Freshly grated nutmeg enhances the dish’s flavor more than pre-ground versions.
- Preheat the Oven: Make sure your oven is fully preheated to 400°F (200°C) before baking to achieve a perfectly browned top.
- Cheese Substitutions: If Gruyère isn’t available, Swiss cheese or sharp cheddar can be used as alternatives.
- Bread Crumb Topping: For extra crunch, use fresh bread crumbs mixed with a bit of melted butter before sprinkling on top.
How To Store & Reheat Leftovers
- Refrigerate: Cover leftover zucchini gratin tightly or place it in an airtight container and refrigerate for up to 3 days.
- Reheating: To reheat, place leftover zucchini gratin in a preheated oven at 350°F for about 15-20 minutes until hot and bubbly. Alternatively, individual portions can be microwaved on medium power for 2-3 minutes until warmed through.
Nutrition Fact
Serving Size: 1 of 6
- Calories: 200
- Total Fat: 12.5g
- Saturated Fat: 3.5g
- Cholesterol: 10.6mg
- Sodium: 435.6mg
- Potassium: 516mg
- Total Carbohydrate: 18.5g
- Dietary Fiber: 2.3g
- Sugars: 5.2g
- Protein: 7.9g
Try More Recipes:

Julia Child Zucchini Gratin
Description
This delicious julia child zucchini gratin is a creamy and comforting dish featuring tender zucchini and caramelized onions, topped with a crispy layer of Gruyère cheese. It’s a quick and easy meal that utilizes common pantry ingredients, offering flexibility for various substitutions. The rich, cheesy crust adds an irresistible texture to this classic recipe.
Ingredients
Instructions
- Drain Excess Moisture: After cooking the zucchini, ensure you drain any excess liquid to prevent the gratin from becoming watery.
- Use Fresh Nutmeg: Freshly grated nutmeg enhances the dish’s flavor more than pre-ground versions.
- Preheat the Oven: Make sure your oven is fully preheated to 400°F (200°C) before baking to achieve a perfectly browned top.
- Cheese Substitutions: If Gruyère isn’t available, Swiss cheese or sharp cheddar can be used as alternatives.
- Bread Crumb Topping: For extra crunch, use fresh bread crumbs mixed with a bit of melted butter before sprinkling on top.
Notes
- Drain Excess Moisture: After cooking the zucchini, ensure you drain any excess liquid to prevent the gratin from becoming watery.
- Use Fresh Nutmeg: Freshly grated nutmeg enhances the dish’s flavor more than pre-ground versions.
- Preheat the Oven: Make sure your oven is fully preheated to 400°F (200°C) before baking to achieve a perfectly browned top.
- Cheese Substitutions: If Gruyère isn’t available, Swiss cheese or sharp cheddar can be used as alternatives.
- Bread Crumb Topping: For extra crunch, use fresh bread crumbs mixed with a bit of melted butter before sprinkling on top.