Tuna Conserva

Instructions

1. Prepare the tuna
   Rinse the tuna chunks under cold water and pat them completely dry with paper towels. Season all sides with 1 teaspoon of kosher salt.
2. Prepare the cooking vessel
   In a heavy-bottomed pot or Dutch oven, add the olive oil, garlic cloves, bay leaves, thyme, rosemary, lemon zest, black peppercorns, remaining salt, and red pepper flakes if using. The pot should be just large enough to hold the tuna in a single layer.
3. Heat the oil
   Heat the oil mixture over low heat until it reaches 180°F (82°C) on a kitchen thermometer. Maintain this temperature throughout the cooking process. Do not let the oil boil or simmer; it should be just hot enough that small bubbles occasionally rise from the herbs and garlic.
4. Cook the tuna
   Gently add the tuna chunks to the heated oil. The tuna should be fully submerged. Cook for about 40-45 minutes, maintaining the temperature between 170-180°F (77-82°C). The tuna is done when it flakes easily with a fork but is still moist.
5. Cool and strain
   Remove the pot from heat and allow the tuna to cool in the oil for 30 minutes. Then, carefully transfer the tuna pieces to a storage container using a slotted spoon. Strain the cooking oil through a fine-mesh sieve to remove the herbs and spices.
6. Finish and store
   Drizzle the lemon juice over the cooled tuna. Pour enough of the strained cooking oil over the tuna to cover completely. The tuna conserva can be refrigerated for up to 2 weeks, with the oil acting as a preservative.