Place your pressure cooker onto high heat.Add the sesame oil, garlic, ginger and chili into the pressure cooker and saute for 2 minutes, until fragrant.Add the Low Carb Hoisin Sauce, tamari, 5 spice and pepper, mix well.Add the pieces of beef chuck and coat in the mixture.Pour the beef stock over and ensure the beef is just covered.Place the lid on your pressure cooker, heat until pressurised then drop to low heat and cook for 1 ½ hours.De-pressurized the cooker and gently remove the beef and shred.Place the remaining liquid in a saucepan and bring to the boil, reduce by half.Add the reduced liquid into the shredded beef.