If you’re on the hunt for a meal that’s both nourishing and bursting with flavor, this Tilapia and Vegetable Casserole Recipe is going to become your new go-to. It perfectly balances tender tilapia fillets marinated in a savory mixture with colorful, sautéed vegetables layered in every bite. The magic of this casserole lies not only in its comforting warmth but also in its vibrant textures and simple yet bold flavors that feel like a celebration of fresh, wholesome ingredients. Whether you’re cooking for family or friends, this dish brings a satisfying twist to dinner time that’s as pretty on the plate as it is delicious.
Ingredients You’ll Need
Gathering the ingredients for this dish is a breeze, and each one plays a special role. The fresh tilapia brings delicate flakiness, the mix of bell peppers, carrots, and onions adds vivid color and natural sweetness, and the marinade with buttermilk and soy sauce infuses layers of tender, savory goodness. Let’s look at everything you’ll want in your kitchen before you get started.
- Tilapia fillets: Around 2 pounds of thawed fillets, which are mild and flaky, perfect for soaking up all the casserole’s delicious flavors.
- Olive oil: For sautéing the veggies and fish, adding a fruity richness and preventing sticking.
- Ketchup: Just a tablespoon for a subtle tanginess; some adventurous cooks opt for sriracha to give it a spicy kick.
- Mayonnaise: Works with ketchup to create a creamy glaze that locks in moisture on the fish.
- Eggs: Two eggs bind and enrich the marinade, helping the flavors penetrate the tilapia.
- Buttermilk: One cup provides acidity that tenderizes the fish beautifully and adds a lovely subtle tang.
- Soy sauce: Two tablespoons for a savory depth, giving the marinade an umami lift.
- Salt and pepper: Just enough seasoning (1/2 teaspoon salt and 1/8 teaspoon pepper) to enhance but not overpower.
- Bell peppers: Two medium-sized, red, orange, or yellow, sliced thin—these bring sweetness, crunch, and vibrant color.
- Carrots: Two medium or large carrots, julienned or grated for texture and a touch of natural sweetness.
- Onion: One medium, sliced into thin half-moons, which caramelizes to add a mellow aroma and robust flavor.
How to Make Tilapia and Vegetable Casserole Recipe
Step 1: Marinate the Tilapia
Begin by whisking together the marinade ingredients—the ketchup (or sriracha if you prefer), mayonnaise, eggs, buttermilk, soy sauce, salt, and pepper. Place your thawed tilapia fillets in a large zip-top bag or bowl and pour in the marinade. Seal or cover, then pop it in the fridge to marinate for about 1 and a half hours. This step is essential as it helps tenderize the fish and infuse every bite with a delicious, layered taste.
Step 2: Prepare and Sauté the Vegetables
While the fish marinates, slice your onion into thin half circles, cut the bell peppers into slender strips, and julienne or grate the carrots. Heat 2 to 3 tablespoons of olive oil in a large skillet over medium-high heat, then sauté the onions for around 3 minutes until they soften and begin to sweeten. Add the bell peppers and carrots and cook for an additional 4 to 5 minutes or until all the veggies have become tender but still hold their vibrant crunch. Set these colorful veggies aside as they will build the lovely layers of your casserole.
Step 3: Lightly Sauté the Tilapia
Drain the marinade from your fish, discarding the excess. Return your now-empty skillet to medium-high heat with another 2 to 3 tablespoons of olive oil. Quickly sauté the tilapia fillets for about 2 minutes on each side merely to develop a golden crust; don’t worry about cooking it through at this stage, as baking will finish the process. This step adds a nice texture and flavor boost to the fish that will make the casserole extra special.
Step 4: Assemble and Bake the Casserole
Grab your casserole dish and start by layering half of the sautéed vegetables evenly across the bottom. Then gently place the tilapia fillets on top of this veggie bed. Mix together 1 tablespoon of ketchup and 1 tablespoon of mayonnaise, and brush this luscious glaze over the fish to lock in moisture and add a creamy tang. Next, cover the fish with the remaining vegetables, season everything lightly with salt and pepper to taste, and cover the dish tightly with foil or a lid. Bake in the oven preheated to 375 degrees Fahrenheit for 15 minutes, allowing all the flavors to marry beautifully and the casserole to finish cooking through.
How to Serve Tilapia and Vegetable Casserole Recipe
Garnishes
Sprinkle a bit of freshly chopped parsley or green onions on top right after baking to brighten the presentation visually and add a fresh herbal note that balances the richness of the dish perfectly. A wedge of lemon on the side also works wonders to add a lively zing when squeezed over just before eating.
Side Dishes
This Tilapia and Vegetable Casserole Recipe pairs wonderfully with simple sides like fluffy steamed rice or creamy mashed potatoes, which soak up all those incredible flavors from the casserole sauce. A crisp green salad with a light vinaigrette can add a refreshing crunch and balance out the meal if you’re looking for something lighter.
Creative Ways to Present
For a casual gathering, serve the casserole straight from the baking dish for a cozy, shareable experience. If you’re aiming for something a bit more elegant, try plating each serving individually with a drizzle of extra marinade glaze or a dash of smoked paprika for color and subtle spice. Adding a small scoop of tangy coleslaw on the side brings a delightful textural contrast, making the whole experience even more enjoyable.
Make Ahead and Storage
Storing Leftovers
If you have leftovers, store them in an airtight container in the refrigerator. The casserole holds up well for 2 to 3 days, making it a convenient option for lunchtime the next day or a comforting dinner waiting for you after a busy day.
Freezing
This recipe can also be frozen if you want to prep in advance. Wrap the casserole tightly with foil and then plastic wrap or place it in a freezer-safe container. It should be good for up to 2 months. When you’re ready to enjoy it, thaw overnight in the fridge before reheating for the best texture and flavor retention.
Reheating
Reheat leftovers in the oven at 350 degrees Fahrenheit for about 15 to 20 minutes until warmed through, ensuring the fish stays tender and the vegetables don’t become mushy. You can also microwave smaller portions but do so gently to avoid drying out the fish.
FAQs
Can I use other types of fish for this casserole?
Absolutely! While tilapia works beautifully due to its mild flavor and firm texture, white fish like cod, haddock, or even catfish would also be delicious options if you want to switch things up.
Is it possible to make this casserole without mayonnaise?
Yes, if you prefer to avoid mayo, you can substitute it with Greek yogurt or sour cream for a lighter, tangy alternative that still helps keep the fish moist during baking.
How can I make the casserole spicier?
For an extra kick, switch the ketchup for sriracha or add a pinch of cayenne to the marinade. You could also toss some diced jalapeños with the vegetables when sautéing for a layered heat profile.
Can I prepare this recipe gluten-free?
Definitely. Just make sure the soy sauce you use is gluten-free, as some brands contain wheat. Everything else in the recipe is naturally gluten-free, making it safe for gluten-sensitive diners.
What’s the best way to ensure the tilapia doesn’t overcook?
Lightly sautéing the fish before baking helps create a protective crust. Also, keep the baking time to the recommended 15 minutes at 375 degrees Fahrenheit, and cover the dish to retain moisture. This combination prevents drying out and keeps the tilapia tender and flaky.
Final Thoughts
This Tilapia and Vegetable Casserole Recipe truly strikes a perfect balance between wholesome comfort and fresh, vibrant flavors that brighten your dinner table. I encourage you to give it a try—whether you’re a seasoned cook or new to fish dishes, its simplicity paired with remarkable taste will quickly make it a cherished favorite. Gather those simple ingredients, enjoy the harmonious layers, and let this casserole bring warmth and joy to your next meal.
Print
Tilapia and Vegetable Casserole Recipe
- Prep Time: 1 hour 30 minutes
- Cook Time: 30 minutes
- Total Time: 2 hours
- Yield: 6 servings
- Category: Casserole
- Method: Baking
- Cuisine: American
Description
This Tilapia and Vegetable Casserole is a flavorful, healthy dish featuring tender tilapia fillets marinated in a tangy blend of buttermilk, soy sauce, and spices, layered with sautéed bell peppers, carrots, and onions, then baked to perfection. It’s a comforting and colorful meal perfect for a family dinner, combining light, flaky fish with vibrant veggies and a creamy ketchup-mayo topping for extra flavor.
Ingredients
Fish Marinade
- 2 lbs tilapia fillets (6–10 count), thawed
- 1 tbsp ketchup (or sriracha as an alternative)
- 1 tbsp mayonnaise
- 2 eggs
- 1 cup buttermilk
- 2 tbsp soy sauce
- 1/2 tsp salt
- 1/8 tsp pepper
Vegetables
- 2 medium bell peppers (red, orange, or yellow)
- 2 medium/large carrots, julienned or grated
- 1 medium onion
Other
- Olive oil for sautéing (about 4-6 tbsp total)
Instructions
- Marinate the Fish: Whisk together the marinade ingredients — ketchup (or sriracha), mayonnaise, eggs, buttermilk, soy sauce, salt, and pepper. Place the tilapia fillets in a large ziplock bag or bowl and pour the marinade over them. Refrigerate and marinate for 1 1/2 hours to infuse the flavors.
- Prepare and Sauté the Vegetables: Slice the onion into thin half circles, cut the bell peppers into thin strips, and julienne or grate the carrots. Heat 2-3 tablespoons of olive oil in a large skillet over medium-high heat. Add the onions and sauté for about 3 minutes until softened. Add the bell peppers and carrots and continue to sauté for another 4-5 minutes until all vegetables are tender. Remove from the skillet and set aside.
- Sauté the Fish: Drain and discard the marinade from the fish. In the same skillet, heat another 2-3 tablespoons of olive oil over medium-high heat. Lightly sauté the tilapia fillets, cooking about 2 minutes on each side until they are golden on the outside but not fully cooked through.
- Assemble the Casserole and Bake: Preheat the oven to 375°F (190°C). In a casserole dish, spread half of the sautéed vegetables as the base layer. Arrange the lightly cooked tilapia fillets over the vegetables. Stir together 1 tablespoon ketchup and 1 tablespoon mayonnaise and brush this mixture evenly over the fish. Cover the fish with the remaining vegetables, season with salt and pepper to taste, then cover the dish tightly with foil or a lid. Bake in the preheated oven for 15 minutes until the fish finishes cooking and the flavors meld.
Notes
- Using sriracha instead of ketchup in the marinade adds a nice spicy kick to the dish.
- Don’t overcook the fish in the skillet; it will finish cooking in the oven during baking.
- Sautéing the vegetables before baking helps retain their color and flavor in the casserole.
- Feel free to switch up the vegetables according to what you have available.
- This dish pairs well with steamed rice or crusty bread to soak up the juices.
