In a pressure cooker add the beef,small onion,chili powder,coriander powder,turmeric powder, fennel powder,pepper powder, ginger garlic paste and curry leaves.Then add cinnamon,star anise,bay leaf,vinegar, salt and two sprig of curry leaves in to it.then mix well with your hands.Cover with the lid and cook over a medium flame with out adding any water,approximately 3-4 whistles depends on the quality of beef.Then switch off the stove and let the pressure goes naturally. (if you are cooking the beef in a normal vessel add sufficient amount of water to cook the beef it will take approximately 60-70 minutes)