private async void doSomething(object sender, RoutedEventArgs e)
    {
        await  FullTrustProcessLauncher.LaunchFullTrustProcessForCurrentAppAsync();
    }

<Applications>
<Application Id="App" Executable="$targetnametoken$.exe" EntryPoint="ProjectCuwp.App">
<Extensions
xmlns:desktop="http://schemas.microsoft.com/appx/manifest/desktop/windows10">
<desktop:Extension
  Category="windows.fullTrustProcess"
  Executable="powershell.exe" />

using Windows.ApplicationModel;