1. Slice the mushrooms in half and the onion into thin slices.
2. Shred or chop the cooked chicken breasts into bite-sized pieces.

1. Heat 1 tbsp of olive oil in a large frying pan over medium-high heat.
2. Add the mushrooms and cook until golden brown, about 3-4 mins, then set aside.
3. In the same pan, add the remaining oil and sauté the onion for 5-6 mins until slightly browned.
4. Stir in the flour and cook for 1 min.
5. Gradually whisk in the hot chicken stock, ensuring no lumps form.
6. Once smooth, add the milk and thyme, stirring until the sauce thickens.
7. Incorporate the sherry, salt, and pepper, adjusting seasoning as needed.
8. Return the mushrooms and add the chicken, cooking for 2-3 mins until heated through.

Serve the chicken mixture over a bed of fluffy rice or pasta, garnished with chopped parsley.