Sprinkle the chicken breasts with some salt & pepper and coat them in the flour.
Separate the garlic cloves and remove the skin. You will be using them whole.
Preheat the oven to 180 degrees C
Add the rapeseed oil and 1 tbsp of the butter to a frying pan. Once the pan is hot, sauté the chicken for 4-5 minutes/side or until it's nice and golden. Take the chicken out of the pan and set it aside.
Reduce the heat to medium, and add the rest of the butter to the pan. Let it melt and then add the garlic cloves. Cook them for 3-4 minutes, stirring often, until they're lightly browned on the outside.
Add the chicken stock, lemon juice, mustard and garlic powder to the pan. Let it bubble for around 4 minutes or until the liquid is noticeably reduced.
Stir in the milk and cream and add the chicken back into the pan. Move to a preheated oven and cook for 10-15 minutes until the chicken is cooked through.
Serve with rice, mashed potatoes or roasted baby potatoes and some steamed vegetables.