Tuna prepared thus ripens in the oil over the course of days, becoming mellow and complex—almost a confit. Serve with crusty bread or boiled potatoes to mop up the sauce.
• 1 teaspoon coriander seed
• 1 teaspoon cumin seed
• 1/2 teaspoon red pepper flakes
• 1 1/4 teaspoon black peppercorns, divided
• 1 1/2 teaspoon kosher salt, divided
• 12–16 ounces super-fresh tuna steak
• 3/4 cup extra-virgin olive oil
• 1/2 cup cider vinegar or white wine vinegar
• 6 garlic cloves, lightly crushed and peeled
• 2/3 cup kalamata olives, pitted and torn in half
• 1 small hot dry red chile
• 1 bay leaf
With a mortar and pestle, crush to smithereens the coriander seed, cumin seed, and red pepper flakes, along with 1 teaspoon each of peppercorns and salt. Pat the tuna dry all over and then rub in the spice mix on all sides. Set aside on standby while you tackle the next step.
In a wide heavy frying pan, heat the oil and vinegar slowly over a low flame. Add the garlic, olives, the whole chile, the bay leaf, and the remaining 1/4 teaspoon of peppercorns and 1/2 teaspoon of salt. As soon as the mixture comes to a simmer, pour it carefully into a wide flat-bottomed non-reactive heatproof container like a casserole or big soufflé dish. Set aside to cool a bit.
Your frying pan will still be oily, so just set it back on the burner and crank it to high. Turn on your exhaust fan. Before a smoke cloud starts up, but just, carefully place the tuna in the pan. Sear for 30 seconds per side for the rarest result, 45 seconds for a little more done, turning carefully with a very thin spatula in between. Turn off the heat, and gingerly transfer the tuna to the crock of marinade, pushing those pesky olives aside so that the fish is completely submerged. The fish and the oil-bath will cool down together.
Let stand a few hours, then serve or refrigerate in airtight containers for up to five days. Best at room temperature.
Recipe developed by Paula Marcoux exclusively for edible South Shore & South Coast.