Cook the pasta one minute shy of the directions on the box and drain.
In a cast iron skillet, add 1 tablespoon of butter.
Add the chicken, salt and pepper in the pan on medium-high heat for 5-7 minutes, stirring once in the middle.
Remove the chicken from the pan and set it aside with the pasta.
Add in 1 tablespoon of butter.
Add in the mushrooms and cook until browned, 5-7 minutes.
Add in 1 tablespoon of butter to the pan with the mushrooms and add your onions.
Cook on medium-low for 5-7 minutes or until caramelized.
Add in the garlic and cook one additional minute.
Add the wine and 1 cup chicken broth and let reduce by ¾ of the liquid (10-12 minutes depending on how hot the skillet and flame are).
Add the sour cream, heavy cream, Parmesan cheese and final tablespoon of butter.
Whisk until it is well combined.
Add in the chicken and pasta and stir to combine.
Serve immediately.
Garnish with additional parmesan cheese and parsley.