Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper.
Clean the cremini mushrooms with a damp cloth and slice them into halves or quarters if they are large.
Slice the chicken breast into 1-inch thick strips to ensure they cook at the same rate as the mushrooms.
In a small bowl, melt the ghee and whisk in the minced garlic, sea salt, black pepper, and fresh thyme.
Place the chicken strips and mushrooms onto the prepared baking sheet and drizzle the garlic-ghee mixture over the top.
Toss everything together until the chicken and mushrooms are thoroughly and evenly coated.
Roast in the oven for 18-20 minutes until the chicken reaches an internal temperature of 165°F and the mushrooms are golden brown.
Remove the pan from the oven, drizzle with fresh lemon juice, and garnish with chopped parsley before serving hot.