There’s something so inviting about a bubbling Spinach Gratin straight from the oven—the glossy surface breaking into golden edges as fragrant steam rises. After three rounds of testing, I nailed down the exact spinach-to-yogurt ratio and timing that keeps every forkful silky smooth yet perfectly set.
Why You’ll Love Spinach Gratin
- A lighter take on a classic gratin with tangy Greek yogurt instead of heavy cream
- Crunchy, nutty panko topping that crackles under your fork
- One-dish side that comes together in under 10 minutes of prep
- Inspired by French comforts, but slimmed down for everyday meals
A Little Background
On my first test run last winter, I learned the hard way that any leftover water in thawed spinach can turn the gratin into a soggy mess. A quick squeeze in a clean towel became my secret. Credit for this makeover goes to that tiny but crucial twist.
Key Ingredients for Spinach Gratin
- Frozen spinach: 2 (10-ounce) packages, thawed and well drained
- Nonfat plain Greek yogurt: 1 (6-ounce) container, adds tang and creaminess
- Grated Parmesan cheese: 1/4 cup, for a savory, umami kick
- Panko breadcrumbs: 1/4 cup, toasting up extra‐crisp
- Yellow onion & garlic: sautéed, build the flavor base
- All-purpose flour: 1 tablespoon, thickens the sauce without lumps
How to Make Spinach Gratin
- Preheat the oven to 350°F. Lightly coat a 1.5-quart baking dish with cooking spray.
- Place thawed spinach in a clean kitchen towel; squeeze out as much moisture as you can.
- In a large skillet over medium heat, warm the olive oil. Add onion and cook until translucent, about 3–4 minutes. Stir in garlic; sauté for 30 seconds, until fragrant.
- Sprinkle the flour over the vegetables; cook, stirring constantly, 1 minute.
- Gradually whisk in the milk; continue cooking, stirring, until the sauce begins to thicken, about 2–3 minutes.
- Remove skillet from heat. Stir in Greek yogurt, Parmesan, nutmeg, salt and pepper.
- Gently fold in the drained spinach until evenly coated.
- Transfer mixture to the prepared baking dish. Evenly sprinkle the panko breadcrumbs over the top.
- Bake 20 minutes, or until the gratin is bubbling around the edges and the topping is golden.
- Let cool 5 minutes before serving.
Pro Tips & Troubleshooting
- During testing, I found cooking the flour a full minute prevented any chalky taste in the sauce.
- If the panko browns too fast, tent the dish with foil for the last 5 minutes of baking.
- Add a pinch of smoked paprika or nutmeg for an autumnal spin when summer greens aren’t available.
- To halve, use an 8-inch dish and check at 15 minutes; to double, switch to a 3-quart dish and add 5–7 minutes.
Storage & Make-Ahead Guide
Transfer leftovers to an airtight container and chill up to 3 days. I noticed the gratin firms up in the fridge; adding a splash of milk before reheating restores silkiness. Reheat in a 350°F oven until 165°F internal temperature, or microwave in 30-second bursts. Freeze in a sealed container for up to 1 month. Never let sit out more than 2 hours to ensure safety.
Serving Suggestions
This Spinach Gratin shines alongside roasted chicken or grilled fish, and tastes lovely with a crisp lemony arugula salad. It also makes a hearty vegetarian main when topped with a fried egg or dollop of pesto.
Frequently Asked Questions
- How do I make a creamy spinach gratin? You’ll want to squeeze out excess moisture, cook the flour in the aromatics, then whisk in milk before stirring in Greek yogurt and cheese so it turns luxuriously creamy.
- Can I use fresh spinach instead of frozen? Yes—use about 1½ pounds fresh, wilt it down in the pan first, cool slightly and squeeze as you would frozen.
- What can I substitute for Greek yogurt? Full-fat yogurt or sour cream works, but whisk it in off-heat to prevent curdling.
- How do I prevent a watery gratin? Thoroughly drain and press your spinach in a towel; any residual liquid will pool and dilute the sauce.
- Can this gratin be made ahead? Assemble it up to the breadcrumb step, cover tightly and refrigerate up to 24 hours. Add 5 extra minutes to baking time.
- How long does leftover spinach gratin last? Stored in an airtight container in the fridge, it stays good for 3 days; freeze beyond that.
Final Thoughts
I always smile when I slide this Spinach Gratin into the oven—it’s proof that healthy twists can still feel comforting. My favorite way to enjoy it? Paired with lemon-pepper salmon and a glass of crisp white wine. Give it a try and let me know how it turns out!
More Recipes You’ll Love
Spinach Gratin
This lighter Spinach Gratin uses Greek yogurt and panko for a tangy, crispy twist on a classic cheesy side.
Servings 6 servings
Calories 71kcal
Gratin Mixture
- 2 10-ounce packages frozen spinach, thawed and well drained
- 1 tablespoon olive oil
- 1 medium yellow onion diced
- 2 cloves garlic minced
- 1 tablespoon all-purpose flour
- 1 cup milk
- 1 6-ounce container nonfat plain Greek yogurt
- 1/4 cup grated Parmesan cheese
- 1/4 teaspoon ground nutmeg
- Salt and pepper to taste
Topping
- 1/4 cup panko breadcrumbs
Filling
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Heat olive oil in a large skillet over medium heat. Add onion and cook until translucent, about 3–4 minutes.
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Stir in garlic and cook 30 seconds, until fragrant.
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Sprinkle flour over the vegetables and cook, stirring constantly, 1 minute.
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Gradually whisk in milk; continue cooking, stirring, until the sauce begins to thicken, about 2–3 minutes.
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Remove skillet from heat. Stir in Greek yogurt, Parmesan, nutmeg, salt and pepper.
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Gently fold in the drained spinach until evenly coated and transfer to the prepared baking dish.
Baking
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Evenly sprinkle the panko breadcrumbs over the top.
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Bake 20 minutes, or until the gratin is bubbling around the edges and the topping is golden.
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Let cool 5 minutes before serving.
After refrigerating, stir in a splash of milk before reheating to restore creaminess.
Leftovers keep for up to 3 days in the fridge or freeze for up to 1 month.
