One is to choose the right bone. To make bone soup delicious, the selected bones must have meat, bones (in other words, bones) and bone marrow. Therefore, the tubular bone is the most suitable, and both ends of the tubular bone are joints with collagen.
The second is not to drown. Basically, most people like to blanch the meat before making soup. In my opinion, blanching will weaken the taste of meat and can't guarantee the original flavor. So I don't recommend blanching the meat, but soaking it in cold water to remove dirt and some blood on the surface of the meat. The specific operation is to put the meat in tap water, soak it for 5 minutes, then change the water and circulate it for 3 times.
The third is to choose the right ingredients to make soup together. Personally recommend several vegetarian dishes: bitter gourd, pea, lotus root and radish. Because these vegetarian dishes can match the taste of meat well and get rid of the greasy pig blood, colleagues make the pig bone soup more pure, fresh and sweet, and will not hide the original taste of pig bone.
Fourth, don't put any fancy spices, such as star anise and cinnamon. Put at most 2 pieces of ginger to suppress the fishy smell, and then add some pickles or something, and it will be fine.
Fifth, the most important thing is to use a pressure cooker to completely soften the pig bones under high pressure and high temperature, and release the delicious food in the bones.