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

{
  "type": "minecraft:crafting_shapeless",
  "ingredients": [
    {
      "item": "minecraft:gunpowder"
    },
    {
      "item": "minecraft:blaze_powder"
    },
    [
      {
        "item": "minecraft:coal"
      },
      {
        "item": "minecraft:charcoal"
      }
    ]
  ],
  "result": {
    "item": "minecraft:fire_charge",
    "count": 3
  }
}