tastytoasters/src/main/resources/data/tastytoasters/recipes/buttered_toast.json

{
  "type": "minecraft:crafting_shapeless",
  "ingredients": [
    {
      "item": "tastytoasters:toast"
    },
    {
      "item": "tastytoasters:butter"
    }
  ],
  "result": {
    "count": 1,
    "item": "tastytoasters:buttered_toast"
  }
}