There is a CraftTweaker object for tweaking campfire.

I wrote a script to add all furnace recipes which produces food to campfire. The added recipes are displayed in JEI, but they do not function.

(Screenshots are not taken under futuremc-only environment, but this is likely not a compat issue)

Future-MC 1.12.2-0.2.02 · Forge 14.23.5.2852 · Optifine HD_U_F6_pre1

▲ The recipe is displayed properly

▲ CraftTweaked recipes work properly in Smoker

▲ Campfire does not accept CraftTweaked items

You know what? I might be able to add some sort of automatic meat adding function.