Heat butter and olive oil in a large saute pan over medium heat. Add chopped onions and and cook over medium heat until softened, about 3 minutes.
Add minced garlic, thyme, paprika, and sliced mushrooms, and continue cooking until tender and browned, about 5 minutes
Deglaze the pan with the white wine stirring a minute or two.
Add broth, tomato paste, and Worcestershire sauce, and bring to a boil. Reduce heat, and continue cooking until reduced by about 1/3, about 7-10 minutes.
Whisk the sour cream in a small bowl and stir in a small into mushroom mixture. Then stir sour cream mixture into mushroom mixture. (see notes)
Season with salt and both black and white pepper to taste and garnish with fresh chopped parsley.
Serve on top of cooked buttered egg noodles.