Format the SQL output on the SQL tab when using your existing NHibernate assemblies in LINQPad.
Import the NuGet package into LINQPad (press F4 and choose Add NuGet...) and run the sample .linq query to learn more.
Full instructions here: https://tomssl.com/2015/06/30/see-your-sql-queries-when-using-nhibernate-with-linqpad/