Preheat your oven to 400°F and line a large baking sheet with parchment paper for easy cleanup.
Pat the chicken breast dry with paper towels and cut into bite-sized 1-inch pieces.
Clean the cremini mushrooms with a damp cloth and slice them into thick halves or quarters.
In a large mixing bowl, combine the chicken pieces, sliced mushrooms, and minced garlic cloves.
Drizzle the mixture with extra virgin olive oil and sprinkle with dried thyme, dried rosemary, sea salt, and black pepper.
Toss everything together until the chicken and vegetables are evenly coated in the oil and aromatic herbs.
Spread the mixture in a single layer on the prepared baking sheet, ensuring the pieces are not overcrowded.
Roast in the oven for 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F and the mushrooms are golden.
While the chicken roasts, warm the pre-cooked brown rice in a small saucepan or microwave until steaming.
Serve the roasted chicken and mushrooms over the fluffy brown rice and garnish with the grated parmesan cheese.