Take your chicken pieces (manok), half of the minced garlic (bawang), sliced onions (sibuyas), soy sauce (toyo), peppercorns (paminta), and bay leaves (dahon ng laurel), combining them in a large bowl. Using clean hands, gently massage (magmasahe) the marinade into the meat to ensure even coating. Cover the bowl and refrigerate for 3 hours or overnight for best results (mas masarap kung overnight).
Thirty minutes before cooking, remove the chicken from the refrigerator to come to room temperature (hayaang umabot sa tamang temperatura). Drain the chicken but save the marinade (itabi ang pinagbabaran) – we'll use this later.
Heat your oil (mantika) in a large skillet or Dutch oven over medium heat (350°F/175°C). Test if the oil is hot enough by dropping a small piece of potato – it should sizzle immediately. Fry your potato rounds until they turn golden brown (hanggang maging golden brown), about 3-4 minutes per side. Remove them to a paper towel-lined plate (patuyuin sa paper towel). Leave just 1 tablespoon of oil in the pan.
Increase the heat to medium-high (375°F/190°C). Place your marinated chicken pieces skin-side down (balat sa ibaba) in the pan. Let them brown properly (hanggang maging golden brown) on all sides, about 3-4 minutes per side. Don't rush this step – good browning means more flavor (mas masarap). Remove excess oil if needed, leaving about 2 tablespoons in the pan.
Lower the heat to medium (350°F/175°C) and add your remaining minced garlic. Sauté until fragrant (hanggang mabango), but don't let it brown. Now comes an important step: pour in your vinegar (suka) but DO NOT STIR (huwag haluin) for 3-4 minutes. This traditional technique, called 'pangasim', helps mellow the harsh acidity of the vinegar.
After the vinegar has been boiling for a few minutes, pour in your reserved marinade and water (tubig). Bring everything to a boil, then reduce to a gentle simmer (pakuluan nang marahan). Cover the pot and let it cook for 20-25 minutes, or until the chicken is tender and reaches an internal temperature of 165°F/74°C. The meat should easily pull away from the bone (madaling matanggal sa buto).
When the chicken is tender, add your fried potatoes back to the pan. Continue cooking uncovered until the sauce has reduced and thickened enough to coat the back of a spoon (hanggang lumapot ang sarsa). This usually takes about 10 minutes. Taste and adjust the seasoning with salt (asin) if needed. If you find it too sour, you can add a small amount of brown sugar (asukal na pula) to balance the flavors.
Let your adobo rest for 10 minutes before serving. This allows the flavors to settle and the meat to become even more tender. Serve hot over steaming white rice (mainit na kanin), garnished with crispy garlic (sinangag na bawang) if desired. Don't forget to spoon plenty of that rich, dark sauce over the rice – that's where all the flavor is!
Remember, adobo always tastes better the next day (mas masarap kinabukasan), so don't hesitate to make it in advance. The flavors will continue to develop and deepen overnight in the refrigerator.