The name of the widget that is making the magic happen is Details View. What it does is, it allows to hook up any UObject based class to it and specify which property categories it should be displaying. The trick here is to hook it up to the widget itself in the Pre Construct event.
With the above setup, we can simply create properties inside the widget itself and they will automatically be pulled and displayed in the widget window.
Remember to put them in a custom category, otherwise you will not have control over which properties exactly are being displayed.
This is the result after compilation:






That is really useful, and doing that in slate is a pain XD