Take 1 lb. of boneless tuna steaks and pat them dry with paper towels. Drizzle 1 tbsp of vegetable oil (or other neutral oil with high smoke point) and spread all over the tuna with your fingers until evenly coated. Season with freshly ground black pepper and kosher salt on all sides.

Take a skillet (we like to use a cast iron skillet), add in 2 tbsp of vegetable oil (or another neutral oil with high smoke point) and heat over medium-high heat. When the oil is very hot (shimmering, almost smoking), add the tuna pieces and cook for 30 seconds. Flip the tuna steaks over and cook the other side for another 30 seconds. Be careful not to overcook.

Transfer the tuna steaks onto a clean plate and let them rest for 1 minute. Then one by one, transfer to a clean cutting board and cut against the grain into thin 1/4" thick strips. Let them rest in the fridge uncovered to cool completely, a minimum of 1 hour.

When the pre-seared tuna pieces are completely chilled, transfer them to a large non-reactive bowl like glass or stainless steel. Add in 1/2 cup of white vinegar and 1/2 cup of freshly-squeezed calamansi or lime juice. Gently mix so that all the tuna slices are evenly coated in the acidic citrus liquid.

Then add in 1/2 of a small red onion, diced into 1/4" pieces, 2 inches of fresh ginger, peeled and finely minced (about 2 tbsp finely minced), 1 cup of cherry tomatoes, cut in half, 1 tsp of calamansi or lime zest, finely grated, 1 tsp kosher salt, 1 tsp of white granulated sugar, 1/2 tsp ground black pepper, 1/2 cup of the creamy part of full-fat coconut milk. Gently fold everything together till well combined. Cover with plastic wrap and let it rest in the fridge for 20 minutes.

After 20 minutes of marination, take the bowl out of the fridge. Set up a fine mesh strainer over a large bowl, and drain the kinilaw mixture over the strainer. Discard the excess marination liquid. Transfer back to the original bowl it was marinated in.

Add in 2 cups of mangoes, diced into 1/2" pieces, and 3 stalks of scallions, only the green parts, finely chopped. Gently fold till everything is well combined. Transfer to a serving bowl, and serve immediately. Enjoy!