data Provider using simpleRestProvider “The response to ‘getList’ must be like”

I am trying to get some data from a json-server feeded to an express server but I am getting an this error: The response to 'getList' must be like { data : [...] }, but the received data is not an array. The dataProvider is probably wrong for 'getList' ra.notification.data_provider_error at validateResponseFormat (validateResponseFormat.ts:30:1) at useDataProvider.ts:109:1
Json server and the headers:

server.use(cors());
const allowCrossDomain = (req, res, next) => {
  res.header("Access-Control-Expose-Headers", "Content-Range");
  res.header("Content-Range", "cakeData 0:20/*");
  next();
};
server.use(allowCrossDomain);
server.use("/api", jsonServer.router("api/db.json"));

The db.json

{
  "cakeData": [
    {
      "id": 1,
      "imageurl": "https://images.unsplash.com/photo-1674991773078-12a3eab409b2?ixlib=rb-4.0.3&ixid=MnwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8&auto=format&fit=crop&w=627&q=80",
      "name": "cake",
      "description": "information about cake"
    },
    {
      "id": 2,
      "imageurl": "https://images.unsplash.com/photo-1674991773078-12a3eab409b2?ixlib=rb-4.0.3&ixid=MnwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8&auto=format&fit=crop&w=627&q=80",
      "name": "cake",
      "description": "information about cake"
    }
  ]
}

And the react admin component:

      <Admin
        basename="/admin"
        dataProvider={simpleRestProvider("http://localhost:3000/")}
      >
        <Resource
          name="cakeData"
          list={ProductList}
          create={CreateProduct}
          edit={EditProduct}
        />
      </Admin>

What am I missing? using only json-server with middlewares was working but as I feed the json-server to express I get the error mentioned above.
As a sidenote I am using proxy in react to proxy from port 3000 to 5000