Name: Ceviche de mero
Prep time: 30 min
Cook time: 25 min
Total time: 80 min
Cuisine: Peruvian cuisine
Ingredients: 600 g mero fillet — skinless, boneless, suitable for raw use under supplier-verified parasite controls; 150 ml fresh lime juice — strained immediately before use; 180 g red onion — very thinly sliced; 18 g ají limo — deseeded and finely chopped; 10 g cilantro leaves — finely chopped; 6 g fine salt; 1 g ground black pepper; 400 g sweet potato — peeled, in four thick portions; 400 g choclo — cut into four rounds, cob included; 1200 ml water — for boiling accompaniments; drain

Ceviche de mero — Piura-style grouper ceviche with ají limo

Yield 4 cold plates

Prep 30 minutes

Cook 25 minutes

Passive 25 minutes

Total 80 minutes

Ingredients ↓

Overview

Ceviche de mero — Piura-style grouper ceviche with ají limo

Along the northern coast, particularly in Piura, mero is a recognised fish for ceviche. Its firm, clean-tasting flesh is cut into pieces and dressed with fresh citrus, sliced red onion and ají limo. Mero is commonly translated as grouper, although market names may cover more than one species; buy correctly identified, legally sourced fish.

Ceviche is raw fish dressed at the last minute, not fish made microbiologically safe by acid. The lime changes its surface texture and flavour but does not replace safe sourcing, parasite-control measures or a cold chain. The dish therefore calls for fish explicitly sold for raw consumption and handled with validated parasite-control practices by a qualified supplier.

The cooked sweet potato and choclo are served alongside, not mixed into the acidic dressing. That contrast is useful: cool sweetness and the chew of the maize balance the sharp juice and chilli. Keep the fish and bowl cold, and assemble only when every guest is ready to eat.

Ingredients

For the ceviche

600 g mero fillet — skinless, boneless, suitable for raw use under supplier-verified parasite controls
150 ml fresh lime juice — strained immediately before use
180 g red onion — very thinly sliced
18 g ají limo — deseeded and finely chopped
10 g cilantro leaves — finely chopped
6 g fine salt
1 g ground black pepper

Cooked accompaniments

400 g sweet potato — peeled, in four thick portions
400 g choclo — cut into four rounds, cob included
1200 ml water — for boiling accompaniments; drain

Method

Boil the sweet potato and corn.Put sweet potato and four choclo rounds in a saucepan with 1200 ml water. Simmer for 25 minutes, or until both are tender; drain and transfer to shallow covered containers immediately. The sweet potato yields easily to a knife and the corn is tender but not mushy. Time: 25 minutes.
Cool the serving ingredients.Cool the cooked sides in shallow covered containers in a refrigerator at 4 °C or below for 25 minutes. Keep raw-ready fish in its own sealed cold container. The sides feel chilled rather than warm when handled with clean utensils. Time: 25 minutes passive chilling.
Cut and chill the mero.Using a sanitised knife and board, cut the supplier-approved raw-use mero fillet into 2 cm cubes and immediately move the fish into food-safe iced storage at 4 °C or colder. Never leave the raw fish on a counter while slicing the vegetables. The cubes are neat and remain cold, without soft or ragged edges. Time: 8 minutes.
Prepare the sharp garnish.Cut red onion into thin crescents; chop deseeded ají limo and cilantro separately. Squeeze and strain the lime juice immediately before serving. Keep a clean mixing bowl nested over food-safe ice. The onion strands are crisp, and the lime juice has no bitter crushed seeds. Time: 12 minutes.
Dress the ceviche briefly.Place the cold mero in the chilled bowl, toss with 6 g salt, pepper, ají limo, cilantro and 150 ml lime juice for 2 minutes. Fold in the onion, dividing the dressing evenly. The fish surface is lightly opaque while the centre stays raw; the cubes remain chilled. Time: 2 minutes.
Serve without holding.Divide the ceviche and juices among four chilled plates. Put one sweet potato portion and one choclo round beside each. Serve immediately; do not rely on lime time as a pathogen kill step. The fish is cold and glossy, the onion still crisp and the cooked accompaniments chilled. Time: 3 minutes.

Practical

Practical guidance

Plan the order around cold seafood safety rather than a long marinade. Cook the sweet potato and corn first and chill them completely; make the dressing only after the fish is safely ready. Use a clean dedicated board for raw fish and discard raw ceviche remaining after service rather than treating it as a make-ahead dish. A seller’s statement that fish is merely “fresh” is not enough: ask whether it is prepared for raw consumption with appropriate parasite controls and cold storage. Do not replace mero with a different fish while keeping the same dish name. If safe raw-use mero cannot be sourced, cook the fish fully to 63 °C for a different cooked-fish dish instead.

Control points

Juice tastes bitterThe limes were squeezed aggressively over pith or seeds. Press gently and strain just before mixing.
Fish softens and loses shapeCeviche was assembled too early or the fish was kept warm. Keep all components cold and dress immediately before serving.

Nutrition per 150 g raw fish plus one sweet-potato portion and one corn round

Serving size150 g raw fish plus one sweet-potato portion and one corn round
Caloriesapproximately 355 kcal
Carbohydrates32 g
Protein36 g
Fat9 g
Fibre4 g
Sodiumapproximately 680 mg

Allergens and food safety

Raw mero presents parasite and bacterial risks. Obtain it from a qualified supplier with documented parasite control and hygienic cold storage; citrus is not a safe cooking substitute and freezing does not kill every pathogen. Keep at 4 °C or colder and serve at once. Pregnant people, young children, older adults and immunocompromised people should avoid raw seafood. Fish is an allergen.

Closing

Result: Cold-cut mero dressed with freshly squeezed lime, red onion and ají limo, served promptly with cooked sweet potato and choclo.
Decisive control: The limes were squeezed aggressively over pith or seeds. Press gently and strain just before mixing.