Cut the chicken breasts into large chunks, then add the flour in a bowl and coat well all the chicken pieces. Set aside.
In a skillet, add the tablespoon of butter and turn on the heat. When it melts, add the chicken pieces and brown on all sides.
Add the lemon juice, then let the chicken absorb it for about 30 seconds, then add the milk. It may curdle a bit but don't worry, keep stirring with a wooden spoon and it will turn into a smooth cream after it simmers for a few minutes.
Season with salt, and black pepper to taste. Mix well and bring to a simmer, then turn down the heat and let the sauce reduce for 10-15 minutes until creamy.
Serve immediately with freshly chopped parsley.
Notes
Storage: You can store leftovers in an airtight container in the fridge for up to 3 days. You can also freeze leftovers for up to 3 months. Thaw in the fridge overnight and reheat in the microwave or in the stove. Add a bit more milk if needed.