Cut the chicken breast into thin, smaller slices and season on both sides with salt and ground black pepper. Keep aside.
1 Chicken Breast, Salt, Black Pepper Ground
Heat up a large skillet and melt half of the butter. Stir in onion slices and sauté over a medium heat setting until they get a bit soft.
6 Tablespoon Butter
Stir in chopped garlic and mushroom slices. Cook briefly to soften the mushroom slices.
Reduce the heat setting a bit and add the seasoning, the bay leaf piece, the thyme, the ground rosemary, the salt, and the black pepper.
1 Inch Bay Leaf, 1 Tablespoon Thyme Dried, ¼ Teaspoon Rosemary Dried Ground, ⅛ Teaspoon Black Pepper Ground, ¼ Teaspoon Salt
Mix and sauté for a few minutes on a medium-high flame so that the mushrooms get a bit soft.
Reduce the heat fully and make some space in the center to drop in the remaining butter. Place in the chicken pieces and cook them on all sides on a medium heat setting.
6 Tablespoon Butter
Spread the mushrooms from the corner of the pan over the chicken and pour in the milk over that. Stir and mix in the Dijon mustard.
1 Cup Milk, 1 Tablespoon Dijon Mustard
Simmer down your chicken and mushrooms over a medium-high flame for a few minutes or until you are satisfied with the consistency of the sauce and the look of your mushrooms and chicken.