How to track function return value in Dart

I need to track a String function return value in Dart/Flutter program.

My program is working, but I cannot figure out what my function is doing.

I need to see a function return value like ‘abc’ or blank or something else.

Using breakpoints does not show the value.

Do you know what I could use to see the actual value?

If I know the actual value, then I could easily see what my function code is doing wrong.

Thank You