Rotten Flesh can be cooked in a furnace, smoker, or on a campfire. The result is Cooked Flesh which fills more hunger points and has a greater saturation. Cooked Flesh does not fill as many hunger points as steak, grants a brief bit of weakness when eaten, and takes longer than most food items to cook.
You can also make bone broth with a bone and bowl. This food item does not fill much of your hunger bar and has little saturation. However, it does give a little bit of regeneration.
Combine bone broth and two cooked flesh to make Flesh Soup. You get more more hunger points filled, the saturation is greater, and you also get regeneration. However, the weakness effect has been doubled.
This mod makes a good edition to zombie apocalypse modpacks (where a lot of rotten flesh is present) and it makes a good quality of life mod as well.
Feel free to include this in your modpacks.