Sauce:
Fry the garlic in the leftover pan juices until fragrant (about 1 minute). Reduce heat to low heat, and add the mustard and half and half (or cream).
Bring the sauce to a gentle simmer and add in any remaining mushrooms and parmesan cheese. Allow the sauce to simmer until the parmesan cheese has melted slightly. (If the sauce is too runny for your liking, add the cornstarch/water mixture into the centre of the pan and mix through fast to combine into the sauce. It will begin to thicken immediately).
Season with a little salt and pepper to your taste. Add in the parsley and the chicken back into the pan to serve.
Enjoy
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