Unable to PUT JSON using ADF Dataflow, the error is "the JSON value could not be converted to System.Collections.Generic.List"

Question

Using a dataflow, I want to "sink" my transformed data to a microservice hosted in ADF. After I transformed my data, I'm using a REST linked service as my "sink":

This is the data model the endpoints requires:

[
  {
    "id": "string",
    "bal": 0,
    "fund" "string",
    "date": "string"
  }
] 

However, when I execute this dataflow, I get the following error: The JSON value could not be converted to System.Collections.Generic.List.

How can I submit ALL of the transformed data as one PUT payload as a list of objects? Debugging it, it seems to want to send it as just an object, like this:

{"fund":"ABC","id":"123","bal":0.0,"date":"2024-03-20"}

Instead of:

[
  {"fund":"ABC","id":"123","bal":0.0,"date":"2024-03-20"},
  {"fund":"DEF","id":"234","bal":0.0,"date":"2024-03-20"},
  {"fund":"GHI","id":"345","bal":0.0,"date":"2024-03-20"}
]

How can I send it the way the endpoint requires it?