import crafttweaker.api.registries.ICookingRecipeManager;

furnace.removeRecipe(<item:mapperbase:steel_ingot>, <item:minecraft:iron_ingot>);
blastFurnace.removeRecipe(<item:mapperbase:steel_block>, <item:minecraft:iron_block>);
blastFurnace.removeRecipe(<item:mapperbase:steel_ingot>, <item:minecraft:iron_ingot>);
blastFurnace.removeRecipe(<item:mapperbase:steel_nugget>, <item:minecraft:iron_nugget>);

craftingTable.removeRecipe(<item:mapperbase:steel_boots>);
craftingTable.removeRecipe(<item:mapperbase:steel_leggings>);
craftingTable.removeRecipe(<item:mapperbase:steel_chestplate>);
craftingTable.removeRecipe(<item:mapperbase:steel_helmet>);