Tuna steak

Ingredients

The fish

• 4tuna steaks
• about 200 g each
• 2cm thick
• very fresh, deep red
• yellowfin or skipjack

The marinade

• juice of 2 limes
• 4 clovesgarlic, crushed
• 1 teaspoonsalt
• half a teaspoon black pepper
• 2bay leaves, crumbled
• 2 tablespoonsolive oil

The onions

• 3large onions
• sliced into rings
• 3 tablespoonsolive oil
• 2 clovesgarlic, sliced
• 1bay leaf
• 2 tablespoonswhite wine vinegar
• a pinch of sugar
• salt and pepper

Sometimes added

• 1green pepper, sliced
• 2tomatoes, chopped
• a pinch of paprika
• a little malagueta chilli
• or piri piri

To serve

• boiled or fried potatoes
• or plain white rice
• or fried plantain
• lime wedges
• a simple green salad

Directions

1. Check your own country’s advice if relevant. Check a current sustainability guide if it matters. Fresh tuna should be deep red or pink. Brown or grey patches mean it is old. It should smell of clean sea and nothing more. Use the fish the day you buy it. Discard fish that smells peppery or sharp. Mix the lime juice, garlic and seasoning.
2. Add the crumbled bay and the olive oil. Rub it over both sides of each steak. Let it sit for fifteen to twenty minutes. Do not marinate tuna in acid for longer.
3. Slice the onions into thick rings. Thick rings hold their shape better. Heat the oil in a wide frying pan. Add the onions with a pinch of salt. Cook them slowly over a medium-low heat. Give them a full twenty minutes. Stir them gently from time to time. They should turn soft, sweet and golden.
4. Add the sliced garlic and bay leaf. Add the green pepper if you are using it. Cook it until it softens as well. Let it bubble and reduce for a minute.
5. Season with salt and black pepper. Add a pinch of paprika if you like. Add malagueta chilli for heat. Set the onions aside and keep them warm. Take the steaks out of the marinade. Pat them dry with kitchen paper. Add a little oil to the hot pan.
6. Lay the steaks in away from you. You should hear a sharp sizzle at once. Turn the steaks over once only. Do not move them while they sear. Lift one edge to check the colour.
7. Take them out and let them rest briefly. Two minutes of resting is enough. Put one steak on each warmed plate. Pile the warm onions over the top. Spoon over any juices from the pan. Squeeze fresh lime over everything. Serve boiled or fried potatoes alongside. Leftovers keep a day in the fridge.

Technique

• Tuna is very easy to overcook, and overcooked tuna is dry and grey with the texture of tinned fish. Ninety seconds a side gives a rare centre; four minutes a side cooks it through. Cape Verdean home cooking often cooks it through and restaurants abroad often serve it rare — both are legitimate.
• Tuna develops histamine if it is kept warm, which causes scombroid poisoning: flushing, headache, nausea. Cooking does not destroy histamine, so the cold chain is what protects you. Buy from a seller with good refrigeration, get it home cold, use it the same day, and discard fish that smells peppery or sharp.
• Do not marinate tuna in lime for more than twenty minutes. The acid cures the surface, turning it opaque and firm — that is ceviche, a different dish.
• Pat the steaks dry before they hit the pan. Wet fish steams rather than sears, and the crust is the point.
• Cook the onions first and set them aside. They need twenty slow minutes; the fish needs three. Rushing the onions over high heat makes them harsh.
• Rare fish carries a small parasite risk that freezing reliably eliminates. Pregnant women and anyone immunocompromised should have fish cooked through.
• A rainbow sheen on tuna flesh is normal and is not a sign of spoilage. Brown or grey patches are.
• Cape Verde imports most of its food, and drought and famine drove an emigration so large that more Cape Verdeans live abroad than at home. In that context, cheap fresh fish from local waters matters more than it would elsewhere — even though most of the wider fishery’s value leaves the country with foreign fleets.

Substitutions

• Swordfish or mahi-mahi replace tuna and take the same treatment, though both need cooking through.
• Frozen tuna steaks work; thaw them slowly in the fridge and dry them very thoroughly.
• Red wine vinegar or lemon juice replaces white wine vinegar in the onions.
• Piri piri or any hot chilli replaces malagueta.
• Rice, potatoes or fried plantain are all standard accompaniments and none is more correct.
• The green pepper and tomato are optional additions to the onions rather than requirements.

Variations

• Atum de cebolada is the fuller onion-stewed version, where the tuna simmers in the onion sauce rather than being seared separately.
• Cachupa, the Cape Verdean maize and bean stew, is the national dish and is often served with fish alongside.
• A grilled version, cooked over charcoal at beach restaurants, is common and needs the same short timing.
• Tuna cooked with tomato and potato into a stew is made in island households.
• Portuguese atum de cebolada is the direct relative on the mainland.
• Some cooks add a splash of white wine to the onions, which is a restaurant touch.

History

Cape Verdean waters are a major tuna fishery, and seared tuna with onions is the cheapest fresh protein on the islands.

Frequently asked questions

What is Tuna steak?

Tuna steak is a main from Cape Verde: seared tuna with onions, the islands’ everyday protein. Cape Verdean waters are a major tuna fishery, and seared tuna with onions is the cheapest fresh protein on the islands.

How long does Tuna steak take to make?

Tuna steak takes 15 minutes of preparation and 15 minutes of cooking. The recipe makes serves 4. It is rated easy to make.

What can I substitute in Tuna steak?

Yes, within limits. Swordfish or mahi-mahi replace tuna and take the same treatment, though both need cooking through. Frozen tuna steaks work; thaw them slowly in the fridge and dry them very thoroughly. Red wine vinegar or lemon juice replaces white wine vinegar in the onions. Piri piri or any hot chilli replaces malagueta. Rice, potatoes or fried plantain are all standard accompaniments and none is more correct. The green pepper and tomato are optional additions to the onions rather than requirements.

What is the most important thing to get right in Tuna steak?

Add the crumbled bay and the olive oil. Rub it over both sides of each steak. Let it sit for fifteen to twenty minutes. Do not marinate tuna in acid for longer.