Heat the poultry stock in a saucepan. Add the beans and cook gently in a closed saucepan for about 15 minutes.
In the meantime, cut the chicken breast fillet across the grain into fine strips and fry in a pan in hot butter or margarine over high heat for about 3-4 minutes. Season with salt and pepper. Deglaze with white wine and add to the beans.
Add the cream and crème fraiche, bring to the boil and bind with the sauce binding agent. Season with salt, pepper and sugar.
Pluck the basil from the stems, roughly chop it and add to the ragout. Serve immediately. Jacket potatoes or baguettes go well with it.