Start by thoroughly cleaning the pork lungs (baga ng baboy) and heart (puso ng baboy) under cold running water. Pat them dry with paper towels. Using a sharp knife, mince both organs very finely (tinadtad) – each piece should be no larger than ¼ inch. This fine mincing is crucial for achieving the right texture.
Place the minced organs in a bowl and combine with native vinegar (suka) and salt (asin). Let this mixture marinate for 20 minutes at room temperature. This step helps remove any gamey smell (lansa) from the meat.
While the meat marinates, prepare your vegetables. Finely dice the white onion (sibuyas) and mince the garlic (bawang). Cut the carrots (karot) into small, uniform cubes. Chop the green and red bell peppers (siling pangsigang) into small pieces. Finely chop the Thai chili peppers (siling labuyo).
Set a heavy-bottom pan or cast iron skillet (kawali) over medium-high heat (180°C/350°F). Add cooking oil (mantika) and wait until it begins to shimmer. Add the diced onions and cook for 5 minutes, stirring occasionally until they become translucent (malinaw). Add the minced garlic and cook for 2 minutes more until fragrant (mabango).
Add the marinated meat mixture to the pan. Cook at medium heat (160°C/320°F) for 20-25 minutes, stirring occasionally (haluin paminsan-minsan) to prevent the meat from sticking to the bottom. The liquid will gradually reduce during this time.
As the liquid reduces, you'll notice the meat starting to brown. Continue cooking until you hear the signature crackling sound (pulutok). This is a crucial stage that indicates the dish is developing its characteristic texture. The oil will begin to separate and form small orange droplets.
Once you hear the consistent pulutok sound, add the carrots first and cook for 3 minutes. Then add both the bell peppers and Thai chilies. Cook everything together at medium heat (160°C/320°F) until the vegetables are tender-crisp, about 3-5 minutes more.
Taste and adjust the seasoning with additional fish sauce (patis) and vinegar if needed. The final dish should have a perfect balance of spicy and tangy flavors, with slightly crispy edges (magaspang) while remaining tender (malambot) in the center.
If serving as pulutan, transfer to a sizzling plate and serve immediately with ice-cold beer and spiced vinegar (sawsawang suka) on the side. If serving as a main dish, plate with steaming white rice (mainit na kanin) and garnish with fresh tomato and onion ensalada.
For storing, let the bopis cool completely before transferring to an airtight container. It will keep in the refrigerator for up to 3 days. When reheating, use a pan over medium heat (160°C/320°F) with a small amount of oil until you hear the pulutok sound again. Never use a microwave, as this will make the meat tough and rubbery.
If your bopis becomes too dry (masyadong tuyo) during cooking, add 2-3 tablespoons of water or stock and reduce heat to 150°C/300°F. If it's too wet (masyadong malabnaw), increase heat to 190°C/375°F and continue cooking until the excess liquid evaporates and you achieve the desired consistency.