MineAssets/1.12.2/assets/minecraft/recipes/coal_block.json

{
  "type": "crafting_shaped",
  "pattern": [
    "###",
    "###",
    "###"
  ],
  "key": {
    "#": {
      "item": "minecraft:coal",
      "data": 0
    }
  },
  "result": {
    "item": "minecraft:coal_block"
  }
}