Prepare pasta and put aside.
In a medium-hot sauté pan, add the olive oil, chopped garlic, and sliced mushrooms. Sauté until garlic starts to turn golden brown, then add white wine and reduce the liquid in the pan by half. Add the tomatoes and stock and let the flavor simmer for 3 minutes. Add butter, grilled chicken, baby spinach, and salt and pepper to taste. When the spinach has wilted and turned a dark green toss the cooked fresh pasta with the sauce, adding the fresh basil. Pour pasta into a bowl and top with fresh shredded Pecorino Romano cheese.