Add mushrooms and 2 teaspoons thyme, cook for 5 minutes. Pour in wine and allow to cook for 3 minutes.
Sprinkle mushrooms with flour, mix well and cook for 2 minutes. Add stock, mix again and bring to a boil. Reduce heat to low-medium heat, season with salt, pepper and crumbled bouillon cubes.
Cover and allow to simmer for 10-15 minutes, while occasionally stirring, until thickened.
Reduce heat to low, stir in cream or half and half. Allow to gently simmer (do not boil). Adjust salt and pepper to your taste.