What you need to do, is create a new Class, let's say you call it MyCustomRecipe. That class then needs to extend AbstractBrewingRecipe, and override the isIngredient (and in your case, the isInput) methods. Then, instead of doing this:
BrewingRecipeRegistry.addRecipe(PotionUtils.addPotionToItemStack(new ItemStack(Items.POTIONITEM), PotionTypes.AWKWARD), new ItemStack(ModItems.ESSENCE_OF_UNDEATH), new ItemStack(ModItems.INK_OF_INNERVATION));
you do the following:
BrewingRecipeRegistry.addRecipe(MyCustomRecipe);