Pat pork belly dry with paper towels
Score the skin in shallow lines (if the skin is on)
Season with salt, black pepper, and optional garlic powder or paprika
Place on a rack over a sheet pan, skin-side up
Refrigerate uncovered 4–24 hours (optional but recommended)
Preheat oven to 300°F / 150°C
Roast 2 1/2–3 1/2 hours until the fat is rendered and the meat is tender
Increase oven to 450°F / 230°C
Roast 15–30 minutes until the skin is crisp and blistered
Rest 10–20 minutes
Slice and serve
Optional method for extra crisp skin: cover skin with coarse salt during the low-and-slow phase, then brush off before the high-heat phase
Optional braise method: sear pork belly in a hot pan 3–5 minutes per side, then bake covered at 300°F / 150°C for 2 1/2–3 hours, uncover for 15–30 minutes at 450°F / 230°C to crisp
Optional glaze: in the last 10–15 minutes, brush with a glaze (honey/soy, hoisin, or BBQ), then broil 1–3 minutes if needed