Spinach Greek Chicken Casserole

I didn’t grow up eating a lot of Greek food, but once I discovered the combination of feta cheese, kalamata olives, and oregano, I was hooked. There’s something about those flavors together that just works—salty, tangy, and a little bit earthy all at once.

This casserole is what happens when you take those classic Greek ingredients and mix them into a dinner that actually fills everyone up. It’s got pasta, chicken, tomatoes, and spinach all baked together with plenty of cheese on top. My kids will eat it, which is saying something, since they usually pick out anything green. But when the spinach is mixed in with everything else and covered in melted mozzarella, they don’t seem to mind.

What Kind of Chicken Should I Use?

For this Greek chicken casserole, you have plenty of options when it comes to the chicken. Rotisserie chicken from the grocery store is probably the easiest route – just shred it up and you’re ready to go. If you prefer to cook your own, boneless skinless chicken breasts or thighs both work great, and thighs will give you a bit more flavor and stay moister in the casserole. You can also use leftover cooked chicken from another meal, which makes this recipe perfect for using up what’s already in your fridge. Whatever you choose, just make sure the chicken is fully cooked and cut into bite-sized pieces before adding it to the casserole.

Options for Substitutions

This Greek-inspired casserole is pretty forgiving when it comes to swaps:

• Rotini pasta: Any short pasta shape works great here – try penne, rigatoni, or even bowtie pasta. Just cook according to package directions before adding to the casserole.
• Chicken: Use rotisserie chicken for a quick shortcut, or swap in cooked turkey, ground beef, or even chickpeas for a vegetarian version. If using ground meat, brown it first before adding to the dish.
• Kalamata olives: If you’re not a fan of Kalamata olives, try green olives or black olives instead. You can also leave them out completely if olives aren’t your thing.
• Spinach: Fresh spinach, frozen spinach, or even kale all work well. If using frozen, make sure to thaw and squeeze out excess water first.
• Feta cheese: While feta gives this dish its Greek character, you can use goat cheese or ricotta if that’s what you have. The flavor will be a bit different but still tasty.
• Mozzarella: Provolone or a mild white cheddar can stand in for mozzarella without any issues.
• Diced tomatoes: Canned crushed tomatoes or even fresh diced tomatoes work just fine as a substitute.

Watch Out for These Mistakes While Baking

The biggest mistake you can make with this casserole is using fully cooked pasta, which will turn mushy after baking in all that tomato sauce – instead, undercook your rotini by about 2 minutes since it’ll continue cooking in the oven.

Another common error is forgetting to drain your diced tomatoes and spinach properly, which can leave you with a watery casserole that lacks the thick, hearty texture you’re after.

Make sure to cover your baking dish with foil for the first 15 minutes of baking to prevent the cheese from browning too quickly, then remove it for the last 10 minutes to get that golden, bubbly top.

Finally, resist the urge to dig in right away – letting the casserole rest for 5-10 minutes after baking allows the sauce to thicken up and makes serving much neater.

What to Serve With Greek Chicken Casserole?

This casserole is pretty hearty on its own, but I love serving it with warm pita bread or garlic bread on the side for scooping up all those tasty Mediterranean flavors. A simple Greek salad with cucumbers, tomatoes, and a lemony vinaigrette is a natural pairing that keeps the theme going without making the meal feel too heavy. If you want something a bit different, roasted vegetables like zucchini, eggplant, or bell peppers work great alongside this dish. You could also keep it super simple with a side of hummus and some fresh veggies for dipping before diving into the main course.

Storage Instructions

Store: This casserole is perfect for meal prep and tastes even better the next day once all the flavors have had time to meld together. Keep it covered in the fridge for up to 4 days, and you’ve got easy lunches or dinners ready to go.

Freeze: You can freeze this Greek chicken casserole for up to 3 months. I like to portion it out into individual servings in freezer-safe containers so I can grab just what I need. Let it cool completely before freezing to maintain the best texture.

Reheat: Warm it up in the oven at 350°F covered with foil until heated through, about 20-25 minutes from the fridge. For individual portions, the microwave works great too. If you’re reheating from frozen, let it thaw in the fridge overnight first for best results.

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 1750-2000
• Protein: 140-160 g
• Fat: 40-55 g
• Carbohydrates: 175-200 g

Ingredients

For the casserole:

• 10 oz rotini (I always use Barilla for the best al dente texture)
• 5 cups chicken (shredded or cut into 1-inch chunks)
• 32 oz tomato sauce (I prefer Hunt’s for its smooth consistency)
• 14 oz diced tomatoes
• 12 oz spinach
• 1/2 cup kalamata olives (sliced into 1/4-inch rounds)
• 1/4 cup red onion
• 1/4 cup green pepper (diced into 1/2-inch pieces)
• 1 1/2 tsp dried basil
• 1 1/2 tsp dried oregano
• 1 tsp minced garlic
• 1/4 tsp red pepper flakes

For the topping:

• 3/4 cup feta (crumbled into small chunks)
• 1 cup mozzarella (I use Sargento shredded for a better melt)

Step 1: Prepare Ingredients and Preheat Oven

• 1/4 cup red onion
• 1/4 cup green pepper
• 1/2 cup kalamata olives
• 1 tsp minced garlic
• 3/4 cup feta

Preheat your oven to 400°F and lightly grease a 9×13 inch baking dish.

While the oven heats, prepare your mise en place: dice the red onion and green pepper into small, uniform pieces, slice the kalamata olives into 1/4-inch rounds, mince the garlic, and crumble the feta cheese into small chunks.

I like to have everything prepped and ready before the pasta goes in the water—it makes the final assembly much smoother and ensures nothing gets overcooked while you’re chopping.

Step 2: Cook the Pasta

• 10 oz rotini

Bring a large pot of salted water to a boil and add the rotini.

Cook according to package directions until al dente—usually around 9-10 minutes.

Drain well in a colander, but do not rinse the pasta; the starch helps it adhere to the sauce and creates a better casserole texture.

Set aside to cool slightly while you prepare the sauce.

Step 3: Build the Casserole Base

• 32 oz tomato sauce
• 14 oz diced tomatoes
• 5 cups chicken
• 12 oz spinach
• 1 1/2 tsp dried basil
• 1 1/2 tsp dried oregano
• 1/4 tsp red pepper flakes
• cooked rotini from Step 2
• diced vegetables and aromatics from Step 1

In a large bowl, combine the tomato sauce, diced tomatoes, shredded chicken, spinach, and all the diced vegetables and aromatics from Step 1 (red onion, green pepper, and garlic).

Add the dried basil, dried oregano, and red pepper flakes, stirring well to distribute the seasonings evenly.

Fold in the cooked pasta from Step 2 and the sliced kalamata olives, mixing until everything is evenly coated and combined.

This layering of flavors—from the tomato base to the herbs and finally the pasta—ensures every bite has balanced Greek flavors.

Step 4: Assemble and Top the Casserole

• casserole mixture from Step 3
• 3/4 cup feta
• 1 cup mozzarella

Pour the entire mixture from Step 3 into the prepared 9×13 inch baking dish, spreading it evenly.

Top with the crumbled feta cheese, distributing it across the surface, then sprinkle the shredded mozzarella evenly over the top.

I always use a combination of both cheeses—the feta adds that authentic Greek tang while the mozzarella ensures a beautiful, even melt that holds the casserole together.

Step 5: Bake and Finish

Place the assembled casserole in the preheated 400°F oven and bake for 25 minutes, or until the cheese is melted and lightly golden on top.

The cheese should be bubbly around the edges and the top should show light browning.

Remove from the oven and let rest for 3-5 minutes before serving—this allows the casserole to set slightly and makes plating cleaner.

Spinach Greek Chicken Casserole

Delicious Spinach Greek Chicken Casserole recipe with step-by-step instructions.

Print Recipe Pin Recipe

Prep Time 15 minutes mins

Cook Time 25 minutes mins

Total Time 40 minutes mins

Servings: 7 servings

Calories: 1875

Ingredients Method

Ingredients

  

For the casserole::

• 10 oz rotini (I always use Barilla for the best al dente texture)
• 5 cups chicken (shredded or cut into 1-inch chunks)
• 32 oz tomato sauce (I prefer Hunt's for its smooth consistency)
• 14 oz diced tomatoes
• 12 oz spinach
• 1/2 cup kalamata olives (sliced into 1/4-inch rounds)
• 1/4 cup red onion
• 1/4 cup green pepper (diced into 1/2-inch pieces)
• 1 1/2 tsp dried basil
• 1 1/2 tsp dried oregano
• 1 tsp minced garlic
• 1/4 tsp red pepper flakes

For the topping::

• 3/4 cup feta (crumbled into small chunks)
• 1 cup mozzarella (I use Sargento shredded for a better melt)

Method

 

1. Preheat your oven to 400°F and lightly grease a 9x13 inch baking dish. While the oven heats, prepare your mise en place: dice the red onion and green pepper into small, uniform pieces, slice the kalamata olives into 1/4-inch rounds, mince the garlic, and crumble the feta cheese into small chunks. I like to have everything prepped and ready before the pasta goes in the water—it makes the final assembly much smoother and ensures nothing gets overcooked while you're chopping.
2. Bring a large pot of salted water to a boil and add the rotini. Cook according to package directions until al dente—usually around 9-10 minutes. Drain well in a colander, but do not rinse the pasta; the starch helps it adhere to the sauce and creates a better casserole texture. Set aside to cool slightly while you prepare the sauce.
3. In a large bowl, combine the tomato sauce, diced tomatoes, shredded chicken, spinach, and all the diced vegetables and aromatics from Step 1 (red onion, green pepper, and garlic). Add the dried basil, dried oregano, and red pepper flakes, stirring well to distribute the seasonings evenly. Fold in the cooked pasta from Step 2 and the sliced kalamata olives, mixing until everything is evenly coated and combined. This layering of flavors—from the tomato base to the herbs and finally the pasta—ensures every bite has balanced Greek flavors.
4. Pour the entire mixture from Step 3 into the prepared 9x13 inch baking dish, spreading it evenly. Top with the crumbled feta cheese, distributing it across the surface, then sprinkle the shredded mozzarella evenly over the top. I always use a combination of both cheeses—the feta adds that authentic Greek tang while the mozzarella ensures a beautiful, even melt that holds the casserole together.
5. Place the assembled casserole in the preheated 400°F oven and bake for 25 minutes, or until the cheese is melted and lightly golden on top. The cheese should be bubbly around the edges and the top should show light browning. Remove from the oven and let rest for 3-5 minutes before serving—this allows the casserole to set slightly and makes plating cleaner.