Ceviche

Ingredients

• Seafood
• Red Onion
• Lime Juice

Method

Ceviche is acid-in-cooking — the citric acid denatures the proteins in raw fish without heat, creating the firm, opaque texture of cooked seafood. This demands two things: impeccably fresh fish and enough lime juice to fully cure the proteins. Skip either and you'll have slippery, half-cooked fish that tastes of nothing.

Start with the onion. Slice it as thinly as a mandoline will go — paper-thin, not coin-thick — then submerge the slices in ice-cold water for 15 to 20 minutes. The cell walls of the onion release their cold-preparation bite into the water; what remains is still sharp, but wettable rather than aggressive. Drain well and set aside.

Cut your fish into 2 cm cubes. Firm white fish — snapper, grouper, or halibut — works best because it takes the acid evenly and holds its structure. (Firmer options like octopus and squid work too; they need longer, closer to two hours, to soften.) Season the raw fish generously with salt — this opens the cell membranes and speeds the denaturing process. Pour enough lime juice over the fish to submerge it completely. Under-juice and the bottom of the bowl stays raw; over-juice and you leach flavour and invite mushiness. The surface should glisten, not slosh. Let this sit in the fridge for 45 minutes to an hour. The flesh will turn from translucent to opaque as the acid does its work. At 45 minutes, the fish will still have a delicate, barely-set centre; at an hour, it's fully firm throughout. Both are correct — choose your texture.

Add the drained onion slices and a pinch of salt, then cover and return to the fridge. Ceviche tastes sharper in the first 30 minutes and develops rounder, deeper flavour after two to four hours as the acid continues working on the fish's umami compounds and the onion softens further into the broth that pools at the bottom. Overnight is too long; the proteins break down into mush. Serve chilled in a shallow bowl with its juice, perhaps with avocado or a whisper of chilli. The juice — the cure — is not waste; it carries all the flavour.