Cook noodles according to package directions.

While noodles cook, melt 2 tablespoons butter in a large nonstick skillet over medium high heat. Add onion and cook until softening, a couple minutes.

Add mushrooms and cook stirring occasionally about 5 minutes.

While mushrooms cook, put chicken, flour, paprika and ½ teaspoon salt and ½ teaspoon pepper in a ziplock or paper bag and shake to coat chicken thoroughly.

Add remaining butter and chicken to pan. Cook until chicken is cooked through about 3 minutes.

Add broth and Worcestershire to pan and bring to a gentle simmer. Cook until thickened about 5 minutes.

Take pan off heat. Pour about ¼ cup of the sauce into the sour cream to temper it. Stir together and then pour back into the pan. Stir to combine.

If it has cooled off too much, return pan to the stove over low heat until hot. Do not boil or the sauce will curdle.