Chicken with tarragon and mustard

I'm always on the look-out for quick weekday meals that cause few headaches but yet still offer a complexity of flavour. Bit of a winner, this one, adapted from a recipe I found in a magazine.

2 tbsp olive oil
350g boneless, skinless chicken breast, cut into bite-size chunks
salt and pepper
170g button mushrooms, thinly sliced
1/2 small onion, chopped very small
100ml white wine
150ml chicken stock
150ml double cream
1 heaped tbsp wholegrain mustard
small bunch chopped tarragon

Colour the chicken in half the oil, then transfer to a plate. Wipe out the pan roughly before adding the rest of the oil. Cook the mushrooms on a high heat until they're nicely coloured, then add the onion and continue for a couple of minutes. Add the wine and let it reduce until it's pretty much all gone. Add the stock, cream and mustard and cook, uncovered, for about 5 minutes until the sauce is thick and about half its original volume. Return the chicken and its juices to the pan and cook for only as long as it takes for the chicken to cook through, perhaps a minute or two. Season with salt and pepper, then add the tarragon. Good with plain boiled rice.

Serves 2.