Take your chicken breasts and seal them in a large ziplock bag. Next take a rolling pin and roll out the chicken. Flatten them by half their original size. Pre-heat your oven on to 400 degrees.

In a large deep pan on high heat, add your olive oil. Then add your sliced spanish onions to the pan. Add some salt and pepper to season the pan. Make sure this pan is hot.

Next add your rolled out chicken to your hot pan and sear the meat on all sides. This locks in all the juices. This should only take a couple of minutes per side. Don't worry about it sticking to the pan. This is a good thing.

Once you have seared all sides place into your pre-heated oven to finish off. About 15 to 20 minutes. Don't remove any of the chicken or onions from this pan. This is key.

Next your going to want to slice all of your mushrooms and the remaining onion your going to chop.

Once your chicken has finished cooking in the oven remove them leaving the onions and add your chopped onions, garlic and salt and pepper to the pan. Add your stock to the pan and bring this to a boil. Don't forget to scrape the baked on bits into the broth. This adds most of the flavour to this dish. At this point add the mushrooms and keep stirring. About 5 minutes or so.

Once you have reduced your broth and have fully cooked your mushrooms go ahead and add your cream. Bring this to a boil stirring all the while. Next add your rosemary and thyme. Stir them in as well. Reduce heat to a simmer until your sauce has thickened.

At this point you can plate your chicken and what ever sides you like. Then pour your sauce over the chicken and enjoy.