Add mushrooms, garlic, nutmeg, basil, oregano, thyme, and bay leaf to the slow cooker. Pour in broth and wine, and stir in desired salt and pepper. Top with cubes of butter, then cover and cook on low until mushrooms are lightly browned and tender, about 3 to 4 hours. Stir 2 or 3 times while cooking.
Serve, garnished with fresh parsley, or freshly grated parmesan if you’re feeling fancy.