Split chicken into breast halves, each weighing roughly 4 ounces. Using a meat mallet, pound chicken to 1 inch thickness. Pat dry and sprinkle with sea salt.

Heat coconut oil over medium-high heat in an enameled cast iron pan.When shimmering, add the chicken breast and cook 3 minutes to golden brown. Flip and cook for an additional 3 minutes.

Pour in the Marsala, broth and thyme. Place sliced mushrooms over the chicken. Cover and simmer for 30 minutes.

Remove from heat and move chicken and mushrooms to one side of the pan. Sprinkle the arrowroot into the liquid and whisk to combine. Sauce will thicken. Transfer to a serving platter and sprinkle with fresh parsley.