There may be several reasons why the twice-cooked pork is dry and hard: 1) The meat is lean and not tender enough; 2) It is not marinated for enough time or the marinating seasoning is not flavorful enough; 3) Heating time Too long or the heat is too high.

The solution is as follows:

1. Choose pork belly with a certain amount of fat, which can ensure a more tender texture.

2. The marinating time should be sufficient to ensure that the seasonings are fully flavored.

3. The heat should be moderate when cooking. Do not heat for too long or the heat is too high to prevent the twice-cooked pork from becoming too dry.

4. Before heating, you can brush a layer of honey or sugar water on the surface of the twice-cooked pork to increase the moistness of the twice-cooked pork.

5. If the twice-cooked pork has been cooked but the texture is still dry and hard, you can try blanch the twice-cooked pork in boiling water and then take it out and eat it. This can make the twice-cooked pork more tender and smooth.