In a large pan over medium heat, add the mushrooms. Do not add any oil or anything yet. Sauteeing them dry first will allow the natural juices to come out. Cook in the pan for about 3-4 minutes until the juices come out. Strain the mushrooms, disgarding the juice. Return mushrooms to the pan and add the diced onion, garlic, butter, olive oil, salt, pepper and worcestershire sauce. Saute for about 4 minutes until onions have turned translucent and mushrooms are starting to caramelize. Add the orzo to the pan and toast it for about 2 minutes, stirring occasionally. Add the beef broth and bring to a boil. Then lower heat to a simmer and cook uncovered for about 10-12 minutes, until orzo has absorbed most of the liquid. Turn off heat and add the cream cheese, sour cream and parmesan. Stir until it is all incorporated. Serve immediately and garnish with more parm and parsley. Enjoy!