Get a frying pan over a medium heat and add a splash of oil. Add the mushrooms and onions, and stir fry for 3 - 5 minutes or until starting to colour. Add the brandy and deglaze the frying pan. Add the creme fraiche and gherkins, slice the chicken and add to the pan too. Stir to combine. Cook for another 3 - 4 minutes until thickened, and season to taste. Garnish with parsley and paprika. Serve with rice.