-
Preheat the oven to 375 F.
-
Cut the chicken in half lengthwise. Generously season with salt and pepper and coat each piece in flour. Shake off excess flour.
-
Add the oil and 1 tbsp butter to a skillet over medium high heat. Cook the chicken in batches, lightly browning each piece of chicken for 3 to 4 minutes per side. Don’t completely cook, will finish in oven.
-
Transfer the chicken to a 9x13 baking pan.
-
Add 1 tbsp butter to the skillet after the chicken is removed. Add in the mushrooms and cook until they are seared and cooked, about 5 minutes. Transfer the mushrooms to the baking dish with the chicken.
-
In the same skillet, over medium heat add the remaining 2 tbsp butter. Once it melts, add the flour and garlic. Cook for about 1 minute, stirring nearly constantly.
-
Pour in the sherry and then slowly whisk in the cream until the flour has dissolved and the sauce is smooth. Cook for a few minutes. Add in a bit of salt and pepper to the sauce.
-
Pour the cream sauce over the chicken and mushrooms.
-
Top the chicken with the cheese slices.
-
Cover the casserole with foil and bake for 20 minutes.
-
Take the foil off and broil for a few minutes until the cheeses has browned.
-
Let the chicken rest for a few minutes and then serve.