Preheat oven to 180 degrees Celsius.
Season the chicken with salt and pepper. Mix in the paprika. Add 1 tablespoon olive oil to a pan and brown the chicken on both sides.
Add the tablespoon of butter to the pan and saute the onion and leeks for a few minutes until it's soft
Add the garlic and thyme and saute for a minute
Add the mushroom and cook on medium-high heat until all the liquid has reduced. Add the chicken stock and cream
Add the chicken and bring to a boil
Cover the pan with a piece of foil and pop into the oven for 20 minutes or until chicken juices run clear
Garnish with fresh parsley. Serve with mashed potatoes