Baked Hake in Tomato Sauce with Spinach and Potatoes
A one-pan baked hake dish combining delicate white fish with a garlicky tomato sauce enriched with capers and oregano. The hake fillets cook gently in the oven atop a bright, tangy sauce while crispy roasted potato cubes and garlicky steamed spinach round out the plate. The interplay of tender fish, acidic tomato, briny capers, and wilted greens creates a balanced, restaurant-worthy meal that feels special yet comes together in under an hour. This version stands out for its efficient oven-cooking method, which allows all components to finish simultaneously, and the inclusion of white wine vinegar added post-cooking for brightness. Perfect for weeknight dinners when you want something that tastes more elaborate than the effort required. Serve with crusty bread to soak up the sauce.
Ingredients
- 2 haddock filletscod fillets1:1white fishfirmadds fish
similar texture and flavor profile
- 1 tin foil
- 2 cloves garlic, peeled and diced
- 1 onion, peeled and diced
- 3 ½ oz spinach
- 1 ¼ lb potatoes, cut into bite-sized cubes
- 1 tbsp capers
- 1 tsp dried oregano
- 1 /4 tsp chilli flakes
- 1 tbsp white wine vinegar
- 1 lb Roma tomatoes, tinned
- olive oil, for cooking
- salt, to taste(optional)
- black pepper, to taste(optional)
- 1 tbsp water, for spinach parcel
- 2 tbsp water, for tomato sauce
Instructions
- 1
Preheat the oven to 400°F.
- 2
Chop potatoes into bite-sized cubes and spread on one half of an oven tray. Drizzle with olive oil, season with salt and pepper, toss to coat, and set aside.
- 3
Peel and dice the onion. Heat olive oil in a medium pot over medium-high heat. Once hot, add onion, season with salt and pepper, and cook until softened.
- 4
While onion cooks, peel and dice the garlic. Lay tin foil on counter, place spinach and diced garlic in the center, add water, and season with salt and pepper. Scrunch foil to seal the packet and place on the other half of the potato tray.
- 5
Once onion has softened, add chilli flakes and stir. Cook briefly, then turn heat off. Add oregano, capers, tinned tomatoes, and water. Stir, season with salt and pepper, and transfer to a baking dish.
- 6
Place fish fillets on top of the tomato sauce, season with salt and pepper, drizzle with olive oil, and place in the oven.
- 7
Place the potato tray and foil packet in the oven alongside the fish.
- 8
Bake all components for 20-25 minutes until fish is flaky and potatoes are tender.
- 9
Open the foil packet and add white wine vinegar to the spinach. Divide potatoes, spinach, fish, and sauce among plates.
Tips
Synchronize cooking times by preparing all components before the oven goes on. Arrange the potato tray and foil packet on the same rack as the baking dish so everything finishes in 20-25 minutes. This prevents the potatoes from becoming mushy or the fish from drying out.
Add the white wine vinegar after the spinach wilts rather than during cooking. This preserves its acidity and brightness, cutting through the richness of the olive oil and sauce without cooking off the volatile compounds that give vinegar its character.
Don't skip the foil packet method for the spinach. The sealed environment steams the greens gently in their own moisture plus garlic-infused water, ensuring tender spinach while preventing it from browning or losing its vibrant color.
Good to Know
Store leftovers in an airtight container in the refrigerator for up to 2 days. Fish dries out quickly, so consume promptly.
Prepare all ingredients (chop potatoes, onion, garlic; assemble foil packet) up to 4 hours ahead. Store in the refrigerator. Cook the tomato sauce base up to 1 day ahead and reheat gently before adding fish.
Serve immediately with crusty bread to soak up the tomato sauce. A crisp white wine like Pinot Grigio or a light rosé complements the acidity and delicate fish. Green salad with lemon dressing provides additional freshness.
Common Mistakes
Do not peel the potatoes; leaving skin on prevents them from falling apart during cooking and roasting.
Do not overcrowd the oven tray; space the potato cubes evenly to allow even browning and crispness.
Do not skip the foil packet seal; an open parcel allows steam to escape, leaving spinach dry and stringy rather than tender.
Do not add vinegar during cooking; adding it after wilting preserves its acidic brightness and prevents flavor loss.
Substitutions
similar texture and flavor profile
thicker fillets may require 2-3 minutes additional cooking
FAQ
Can I use fresh haddock instead of fillets, or different white fish?
Yes. Cod, pollock, halibut, and sea bass work equally well. Match fillet thickness to the recipe (roughly 3/4 to 1 inch). Thicker fillets may need 2-3 minutes extra baking time. Frozen fillets are fine if thawed completely before cooking.
Can I freeze leftovers and how long do they keep?
Fish does not freeze well once cooked; texture becomes mushy upon thawing. Freeze the sauce alone in an airtight container for up to 3 months. Thaw, reheat gently, and top with freshly baked fish. Potatoes and spinach also freeze separately if desired.
What if I don't have white wine vinegar?
Red wine vinegar, lemon juice, or lime juice work as substitutes in equal volume. Red wine vinegar is stronger, so taste before adding more. Lemon juice is brighter and less assertive. Avoid distilled vinegar, which lacks depth. Skip vinegar entirely if nothing available; the tomato sauce provides sufficient acidity.