Preheat your oven to 400°F and line a large baking sheet with parchment paper for easy cleanup.
Slice the chicken breast into even 1-inch cubes and halve the cremini mushrooms so they roast at the same rate.
Spread the chicken and mushrooms onto the prepared baking sheet, then drizzle with the extra virgin olive oil.
Sprinkle the sea salt and black pepper over the mixture and toss thoroughly to ensure every piece is lightly coated.
Roast in the center of the oven for 15 to 18 minutes until the chicken is cooked through and the mushrooms are tender and golden.
While the chicken roasts, melt the ghee in a small saucepan over low heat and add the minced garlic and fresh thyme.
Sauté the garlic for about 2 minutes until it becomes fragrant and slightly softened, being careful not to let it brown.
Remove the sheet pan from the oven and pour the warm garlic-thyme ghee over the chicken and mushrooms.
Toss everything together directly on the pan to emulsify the juices with the ghee, then garnish with fresh parsley and serve.