Carefully cut breasts in half lengthwise to make cutlets. Note 5.
3 boneless, skinless chicken breasts
Cover them with plastic wrap, and pound them to an even thickness with a meat tenderizer, if necessary. Note 6.
Dry the cutlets with a paper towel.
Season the chicken on both sides with salt and pepper.
salt and freshly ground pepper
Add the flour to a shallow medium bowl and dredge the chicken in the flour, shaking off any excess. Note 7.
½ cup all-purpose flour
In a large skillet, heat the olive oil over medium-high heat.
2 tablespoons olive oil
Add the chicken breasts and cook for about 3-4 minutes per side or until they are golden brown and cooked through to an internal temperature of 165 F (74 C). Remove the chicken from the pan and set it aside.
In the same pan, lower the heat to medium. Add the unsalted butter and garlic. Stir and cook until fragrant, about 30 seconds.
2 tablespoons unsalted butter, 3 teaspoons garlic
Add the sliced mushrooms and sauté until the mushrooms release their moisture and turn golden brown, about 4 minutes.
8 ounces mushrooms
Pour in the chicken broth and scrape any browned bits from the bottom of the pan. Let the broth simmer for a few minutes (about 4 minutes) to reduce slightly. Note 8.
1 cup chicken broth
Lower the heat and add the Dijon mustard and tried thyme. Stir in the heavy cream. If needed, season with salt to taste. Simmer the sauce for a few minutes until it thickens and coats the back of a spoon.
1 teaspoon Dijon mustard, 1 teaspoon dried thyme leaves, ½ cup heavy cream
Return the cooked chicken to the pan, coating it with the creamy mushroom sauce. Cook for an additional minute or two to let the chicken absorb the flavors.
If desired, garnish with fresh parsley.
2 tablespoons fresh parsley