1. In a pressure cooking pot, heat vegetable oil until hot. Add garlic and fry until just fragrant. Add the beef shank and cook until browned. (Option: Sear the beef, using a cooking torch. It will give a great taste.)
2. Add carrot, onion and cook for about 5~6min or until slightly wilted.
3. Add bay leaf and water. Cover the lid and lock the pressure cooker. Turn the heat to high. Once the pressure builds up, turn the heat down to low heat and cook at high pressure for about 25 minutes. Turn off the heat and let the pressure come down naturally.
4. Remove the lid, add the seasoning (soy sauce, mirin, black chocolate and curry roux). Using a wooden spoon, dissolve the roux completely. Make sure you stir once in a while so the curry will not get burnt on the bottom.