Here's how to overcome this common gotcha: The default password reset system not working out of the box with Laravel 5.x (as you're not sent the user's password), without having to alter altering vendor/core. Here's how to make it work as you'd expect it to without changing any vendor files.
Firstly create a new notification for your app:
php artisan make:notification ResetPassword
Then open the newly created file: app\Notifications\ResetPassword.php
and make the following changes: