Flutter Initial Installation Experience

Installing Flutter on MacOS and using IntelliJ

https://flutter.io/setup-macos/
From there, just iterate on brew doctor until it stops warning you about things not being installed.
In IntelliJ, I also got the following warning about the Dart SDK
Dart SDF not configured
Of course, when you click on the “Download Dart SDK” link, it points you to install Flutter, which I have done.
Recommendations for Dart Installation
After checking the flutter/bin directory, I confirmed that there was nothing that looked like "dart" in there.
After a bit of searing on “Dart SDK is not configured”, I found that Android Studio users were running into the same thing:
In "Dart SDK path" click in "..." and navigate to flutter bin directory. Under that directory you'll find "cache/dart-sdk". This is the dart sdk path you should use.

Sure enough, in ".../flutter/bin/cache/dart-sdk/bin" were all the dart* binaries and alias scripts.

After that (I was already set up in Xcode for iPhone development), it was trivial to build and deploy a basic test app to the iPhone X Simulator.

Flutter Demo Counter App
Flutter Demo Counter App in iPhone X Simulator