Brocho before eating this:
Generally (with or without mushrooms), Borei Minei Mezonos
However, if it is a clear soup with very few barley, say Shehakol Niyeh Bedvoro on the soup and Borei Minei Mezonos on the barley
Brocho after eating the proper shiur of this (Barley): Al Hamichya [if a proper shiur is only eaten of the soup then say Borei Nefashos]
Source: The Laws of B'rachos (page 380)