minecraft-assets/data/minecraft/recipes/scaffolding.json

{
  "type": "minecraft:crafting_shaped",
  "category": "misc",
  "key": {
    "I": {
      "item": "minecraft:bamboo"
    },
    "~": {
      "item": "minecraft:string"
    }
  },
  "pattern": [
    "I~I",
    "I I",
    "I I"
  ],
  "result": {
    "count": 6,
    "item": "minecraft:scaffolding"
  }
}