Separate the ribs into an individual segment and cut each segment into smaller pieces. I leave mine whole because where I got my pork ribs they don't cut it for you
Mix all ingredients for marinade. Rub the marinade all over the ribs. For the best result, you can marinate them in a zipper bag. They will get evenly marinated. Marinate for at least 2 hours or overnight
Take the ribs out from the ribs for about 1 hour before you plan to start cooking them
Preheat oil enough for deep frying the ribs. When you put a skewer into the oil, it should sizzle and lots of bubbles around it. The oil is ready. Fry the ribs in batches. Fry over medium heat until the ribs are cooked through. Remove from the oil and put on absorbent paper towel. Repeat with the rest of the ribs
Bring the oil back to hot. Fry the ribs in batches again, starting from the ones you fry first. This round is to crisp up the ribs and it shouldn't take long. The ribs will have darker shade of golden brown. Remove from oil into absorbent paper towel. Keep them warm in the oven on a rack
Prepare the coffee sauce:
Mix all ingredients for coffee sauce in a pan. Cook over medium heat until the sauce thickens. Add the fried pork ribs into the sauce and toss to coat. Off the heat. Garnish with some sesame seeds and chopped green onion. Serve immediately
In the U.S. potato starch and potato flour are different. The starch is well, the starch extracted from potatoes. The flour are made by grinding the whole potatoes. The terms potato starch and potato flour may be used interchangeably if you live in Asia. So please double-check before you use it.