Add the chicken pieces to a large bowl (or ziptop bag) and add the flour, paprika, salt and cayenne. Mix to coat all of the chicken pieces well.
Melt the butter in a large nonstick skillet over medium high heat. Add the chicken pieces and cook for 3 minutes, until lightly browned. Add the onion and mushrooms and continue to cook for another 3-4 minutes, until slightly tender. Add the garlic and cook for 1 more minute.
Next, add the chicken broth and bring to a simmer. Cook for 3-4 more minutes, until the chicken is cooked through and the sauce is thickened.
Remove the pan from the heat then stir in the Greek yogurt or sour cream until incorporated into the sauce. Sprinkle with the fresh parsley and serve immediately.
