Add border circular around cachednetworkimage

I wanted to take the following image and add a border around it:

To do so I used the following code inside decoration: BoxDecoration()

ClipOval(
                                    child: CachedNetworkImage(
                                      imageUrl: snapshot
                                          .data!.memberEntity.memberPicture!,
                                      width: _size.width * 0.2,
                                      height: _size.width * 0.2,
                                      imageBuilder: (context, imageProvider) =>
                                          Container(
                                        decoration: BoxDecoration(
                                          shape: BoxShape.circle,
                                          border:
                                              Border.all(color: Colors.black),
                                          image: DecorationImage(
                                            image: imageProvider,
                                            fit: BoxFit.cover,
                                          ),
                                        ),
                                      ),
                                      placeholder: (context, url) =>
                                          const CircularProgressIndicator(),
                                      errorWidget: (context, url, error) =>
                                          const Icon(Icons.error),
                                    ),
                                  ),

The result: