Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Clean the cremini mushrooms with a damp cloth and cut any large ones into halves or quarters.
Slice the chicken breast into even, bite-sized pieces for uniform cooking.
In a large mixing bowl, whisk together the melted ghee, minced garlic, fresh thyme, and fresh rosemary.
Add the chicken and mushrooms to the bowl, tossing thoroughly until every piece is coated in the garlic-ghee mixture.
Season the mixture with sea salt and black pepper, then spread it in a single layer on the prepared baking sheet.
Roast for 18 to 20 minutes, or until the chicken is cooked through and the mushrooms are golden and tender.
Remove from the oven, drizzle with fresh lemon juice, and garnish with chopped parsley before serving.