Combine maltose, Shao Hsing cooking wine, hoisin sauce, five-spice powder, dark soy sauce, and ½ cup (120mwater in a small saucepan. Stir to dilute maltose. Bring marinade to a boil.
Add minced garlic. Reduce heat to medium low and continue to simmer until marinade is thick and syrupy. This should take about 10 minutes. Add sesame oil and allow marinade to cool completely.
Place pork in a zip top plastic bag. Pour half the marinade into the bag. Press out as much air as possible and zip the bag. Allow pork to marinade in the refrigerator for at least 4 hours or overnight if possible.
Preheat oven to 375˚F (190˚C). Line a baking tray with aluminum foil. Place a metal rack on the top.
Remove pork from the refrigerator. Unzip the bag and transfer pork with a pair of tongs onto the metal rack. Roast pork in preheated oven for 25 to 30 minutes.
Carefully remove pork from the oven. Brush remaining marinade onto each strip of pork. Turn and brush the other side with more marinade. Return to the oven and continue to roast for another 15 minutes.
Allow char siu to rest for 10 minutes before slicing and serving.