Combine wine, oyster sauce, sugar, hoisin sauce, honey, and 5-spice powder in a saucepan over medium heat. Bring up to a boil. Lower to a simmer and allow the sauce to thicken slightly, about 10 minutes.
Cut belly into 4 equal pieces and rinse. Pat dry with paper towels.
Add the belly pieces and 4 T of homemade char siu sauce to a resealable plastic bag. Marinate at least 24 hours in fridge.
About 1 to 1½ hours before cooking, remove pork belly pieces from marinade. Reserve the marinade.
Place the pork belly pieces into Fry Pan Basket. Set to 400°F for 10 minutes.
At the end of 10 minutes, baste pork belly with the remaining marinade and return to the fryer at 320°F for an additional 10 minutes. Once cooked, remove pork belly and set aside to rest.
While pork belly is resting, add 3 T char siu sauce with 5 T water to a small saucepan and bring to a boil.
Slice pork belly and drizzle char siu over the top of sliced pork belly then top with sesame seeds.