Spinach Casserole Recipe

This Spinach Casserole is a rich, creamy, and incredibly decadent recipe, which transforms simple spinach into a show-stopping side dish. Made with a velvety three-cheese sauce featuring nutty Gruyère, fresh spinach, and a crunchy fried onion and panko topping, it’s the ultimate comfort food. This is a must-have for any holiday table or special dinner party, ready in about an hour.

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Spinach Casserole Recipe Ingredients

For the Casserole:

• 2 Tbsp. olive oil
• 2 (9-oz.) bags fresh spinach
• 3 Tbsp. butter
• 3 cloves garlic, minced
• 3 Tbsp. all-purpose flour
• 1 1/2 cups whole milk
• 2 oz. cream cheese, softened
• 1 1/2 cups shredded Gruyère cheese
• 1/3 cup grated Parmesan cheese
• Zest of 1 lemon
• 1/2 tsp. kosher salt
• 1/4 tsp. black pepper

For the Topping:

• 1 cup french fried onions, lightly crushed and divided
• 1/2 cup panko breadcrumbs

How To Make Spinach Casserole

1. Prep Oven and Wilt Spinach: Preheat the oven to 350°F. In a large skillet or Dutch oven over medium heat, heat the olive oil. Add the spinach (in batches, if needed) and cook, stirring occasionally, for about 5 minutes, until it is just wilted. Transfer the spinach and all of its juices to a heat-safe bowl and set aside.
2. Make the Cheese Sauce: In the same skillet, melt the butter until it’s bubbly and golden. Add the garlic and flour and stir constantly with a wooden spoon for 2 minutes to create a roux.
3. Thicken the Sauce: Slowly whisk in the milk, salt, and pepper. Continue to cook, stirring frequently, for 5 to 7 minutes, until the mixture has thickened enough to coat the back of a spoon.
4. Add the Cheeses: Reduce the heat to low. Stir in the softened cream cheese until it is completely combined. Add the shredded Gruyère in three batches, making sure each batch is fully melted and incorporated before adding the next. Stir in the Parmesan cheese.
5. Combine and Bake: Add the spinach with all of its reserved juices back to the cheese sauce, stirring until well combined. Stir in half a cup of the fried onions.
6. Top and Bake: In a small bowl, combine the remaining 1/2 cup of fried onions with the panko breadcrumbs. Transfer the spinach mixture to an 8×8-inch baking dish and sprinkle the fried onion and panko mixture evenly over the top.
7. Serve: Bake for 30 to 35 minutes, until the casserole is bubbling and the topping is a deep golden brown. Let the casserole sit for at least 10 minutes to set up. Top with fresh lemon zest just before serving.

Recipe Tips

• How to get a perfectly smooth, non-lumpy sauce? The key is to add your milk to the roux slowly, especially at the beginning, while whisking constantly. This allows the flour to dissolve smoothly without forming lumps. Also, add the cheeses over a very low heat to ensure they melt gently.
• How to get the richest flavor? For the best, most complex flavor, shred your own Gruyère and Parmesan cheese from a block. Pre-shredded cheeses are often coated in starches that can make the sauce gritty and less flavorful.
• Can I make this ahead of time? Absolutely! This is the perfect make-ahead holiday side dish. You can assemble the entire unbaked casserole (without the panko topping), cover it, and store it in the refrigerator for up to a day. Add the topping just before baking and you may need to add 10-15 minutes to the baking time.
• How to prevent a watery casserole? This recipe is designed to be very creamy and uses the natural juices from the spinach. To control the amount of liquid, don’t overcrowd the pan when you are wilting the spinach; this allows some of the water to evaporate while still leaving flavorful juice behind.

What To Serve With Spinach Casserole

This is a rich and decadent side dish that is a staple at holiday meals and special dinners. It pairs perfectly with:

• A Thanksgiving Roast Turkey
• A glazed Holiday Ham
• A simple Roasted Chicken
• A perfectly seared steak

How To Store Spinach Casserole

• Refrigerate: Cover the cooled casserole tightly with foil or transfer it to an airtight container. It will keep well in the refrigerator for up to 4 days.
• Reheat: For the best results, reheat the casserole in a 350°F oven, covered with foil, for 15-20 minutes, until warmed through. This will help re-crisp the top slightly.

Spinach Casserole Nutrition Facts

• Serving: 1/6th of recipe
• Calories: 450 kcal
• Carbohydrates: 25g
• Protein: 18g
• Fat: 32g
• Saturated Fat: 18g
• Sodium: 950mg

Nutrition information is estimated and may vary based on ingredients and cooking methods used.

FAQs

Try More Recipes:

• Creamy Spinach and Red Pepper Stuffed Chicken Recipe
• Spinach with Garlic Chips Recipe
• Elevating Frozen Spinach Recipe