我需要在Dart中解码以下JSON。当我执行解码时，我遇到以下错误。我该如何解决这个问题？

**错误：**type '（Map<dynamic，dynamic>）=> RicettaNew'不是'f'类型'（dynamic）=> dynamic'的子类型
JSON：

[{"name":"ricetta1","values":
[{"key":"item1","value":"3"},
{"key":"item2","value":"8"},{"key":"item3","value":"13"}
,{"key":"item4","value":"18"},{"key":"item5","value":"23"},{"key":"item6","value":"14"},....

字符串

Flutter Code：

var serverlink = "http://207.154.221.255:8600/api/recipes"+"/"+mc.model;
      var request = http.Request('GET', Uri.parse(serverlink));
      http.StreamedResponse response = await request.send();
      if (response.statusCode == 200) {
        var result = await response.stream.bytesToString();
        print("result: "+result);
        var list = jsonDecode(result.toString());
        lista=jsonDecode(result).map((Map m)=> RicettaNew.fromJson(m)).toList();

...
class RicettaNew {
  String name;
  List<Values> values = [];

  RicettaNew(this.name, this.values);

  RicettaNew.fromJson(Map json) {
    name = json["name"];

  }
}

型