Cook onions until soft and then add the carrots, mushrooms and garlic. Add chicken until cooked
Make the sauce by melting the butter and then add the flour and cook for 2 minutes. Then slowly add the stock bit by bit to make a smooth sauce. When it has reached the correct consistency, add to the chicken mix
Either cook on the hob or in the oven for 30 minutes. 5 minutes before the end add the milk. Garnish with the chopped parsley and serve.