Greek Fish with Tomatoes and Onions: Healthy Mediterranean Dinner

This Greek fish with tomatoes and onions is the ultimate dish for anyone craving bold flavors and balanced nutrition. Tender white fish is baked in a rich tomato and onion sauce layered with oregano, paprika, and cumin—a spice combination that brings the Mediterranean right to your kitchen. Packed with protein, naturally gluten-free, and low in calories, this recipe checks all the boxes for a healthy yet satisfying meal.

We developed this dish to highlight how simple ingredients can deliver outstanding results for your health. After testing countless variations, we nailed a version that offers the perfect balance of vibrant flavor and ease of preparation. This is a must-try recipe for busy weeknights when you want a wholesome, delicious Mediterranean-inspired dish ready in under 30 minutes.

Why This Greek Fish with Tomatoes and Onions Is Good for You

• High in protein: The white fish is lean yet packed with high-quality protein to keep you full.
• Rich in antioxidants: Tomatoes provide lycopene, a powerful antioxidant linked to heart health.
• Low carb and gluten-free: Suitable for anyone following a keto, low-carb, or gluten-free diet.
• Healthy fats: Extra virgin olive oil is a fantastic source of monounsaturated fats that support heart health.
• Family-friendly: Kids and adults alike will love this flavorful, nutrient-packed meal.

Wholesome Ingredients for This Greek Fish with Tomatoes and Onions

This easy Greek fish recipe relies on simple, whole ingredients. Let’s take a closer look at some of the standout players:

• White Fish: Choose firm, mild fillets like cod, halibut, or haddock. These are rich in protein and omega-3 fatty acids. For a more sustainable option, look for fish certified by the MSC.
• San Marzano Tomatoes: These provide a naturally sweet, rich flavor that pairs beautifully with Mediterranean spices. If you can’t find San Marzano tomatoes, look for a high-quality canned tomato as an alternative.
• Extra Virgin Olive Oil: One of the cornerstones of Mediterranean cuisine, this heart-healthy oil adds flavor while supporting essential nutrient absorption.
• Spices: Oregano, paprika, and cumin bring depth to the dish. You can substitute smoked paprika for a more robust flavor or adjust spice levels to your preference.

Greek Fish with Tomatoes and Onions Recipe Details

• Servings: 6
• Prep Time: 10 minutes
• Cook Time: 15 minutes
• Total Time: 25 minutes
• Cuisine: Greek
• Course: Entree

Ingredients for Greek Fish with Tomatoes and Onions

• 2 tablespoons extra virgin olive oil
• 1 large yellow onion, halved and thinly sliced into half-moons
• 2 large garlic cloves, minced
• 1 (28-ounce) can of whole peeled tomatoes (preferably San Marzano)
• 2 teaspoons dried oregano, divided
• 1 teaspoon sweet paprika
• 1/2 teaspoon ground cumin
• Kosher salt and black pepper, to taste
• 2 pounds white fish fillet (such as halibut or cod)
• 2 lemons, divided
• 1/4 cup fresh parsley, chopped

How to Make Greek Fish with Tomatoes and Onions

1. Preheat your oven to 400°F and position the rack in the middle.
2. In a large oven-safe pan or skillet, heat the extra virgin olive oil over medium-high heat until shimmering.
3. Add the sliced onions and season with a pinch of kosher salt. Sauté, stirring occasionally, for about 7 minutes or until softened and lightly golden.
4. Add the minced garlic and cook for 1 minute until fragrant. Then add the canned tomatoes with their juices. Break the tomatoes up with a wooden spoon for a chunky sauce.
5. Season with oregano, black pepper, and a pinch of salt. Bring the sauce to a boil, then reduce the heat to a simmer for around 10-15 minutes.
6. While the sauce cooks, pat the fish fillets dry. Generously season both sides with kosher salt, paprika, cumin, and additional oregano.
7. Squeeze the juice of one lemon over the fish fillets for a bright, citrusy flavor.
8. Once the sauce has thickened slightly, nestle the fish into the tomato mixture, ensuring each fillet is well-covered with sauce.
9. Transfer the skillet to the oven and bake for 15-25 minutes. The fish is ready when it flakes easily and turns opaque.
10. Remove from the oven, garnish with freshly chopped parsley, and serve with lemon wedges on the side for squeezing over.

How to Customize This Greek Fish with Tomatoes and Onions for Your Diet

• Keto/Low Carb: This recipe is naturally low-carb, but avoid serving it with bread or rice to keep it keto-friendly.
• Vegan: Substitute white fish with firm tofu or seitan for a plant-based version.
• Nut-Free: Great news—this recipe is naturally nut-free as is!
• Make It Spicy: Add a pinch of red pepper flakes to the tomato sauce for a bit of heat.

Our Team’s Tips for the Best Greek Fish with Tomatoes and Onions

• Choose the Right Fish: Firm white fish like cod holds up beautifully under the saucy, baked preparation.
• Use Fresh Herbs: While dried oregano boosts flavor, topping the dish with fresh parsley adds brightness and contrast.
• Don’t Overbake: Keep an eye on your fish to avoid drying it out. Start checking for doneness at 15 minutes.
• Serve with Complementary Sides: Pair with a Greek salad or roasted vegetables for a complete meal.
• Batch Cooking: Double the sauce recipe! It stores well for up to 5 days and makes a great base for other proteins.

Greek Fish with Tomatoes and Onions FAQs

What is Psari Plaki?

Psari Plaki is a traditional Greek dish combining fish with a savory tomato and onion sauce, often baked for maximum flavor.

Can I use frozen fish?

Yes! Just thaw the fish overnight in the fridge or under cold running water, then pat it dry before seasoning.

What makes this a healthy Mediterranean fish dish?

It’s low in fat, high in protein, and uses heart-healthy olive oil and tomatoes packed with antioxidants.

How do I store leftovers?

Store in an airtight container in the fridge for up to 2 days. Reheat gently to avoid overcooking.

Can I make this a quick fish dinner?

Definitely! With just 25 minutes from start to finish, this recipe is perfect for busy nights.

This Greek fish with tomatoes and onions fits into a variety of lifestyles while delivering vibrant, Mediterranean flavors in every bite. What’s your favorite way to incorporate more healthy meals into your week? Let us know in the comments below!