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

Scale

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)

Cook Mode Prevent your screen from going dark

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.