Soak mushrooms in hot water to cover until soft about 20 minutes and drain, reserving ½ cup of the liquid.
Rinse mushrooms and cut off tough mushroom
stems.
Rinse chicken; pat dry. Sprinkle with pepper; dust with flour.
Heat oil in wide non-stick frying pan over medium-high heat.
Add chicken; cook, turning once until well browned on both sides. Lift chicken from pan; set aside.
Add garlic, tomatoes, and mushrooms to pan; stir for 1 minute.
Add reserved ½ cup mushroom liquid, broth, wine and 3 tbsps. (tablespoons) of vinegar. Boil for 3 minutes; remove from heat.
Bland cornstarch and water; stir into sauce in pan. Return chicken to pan, spooning sauce over it.
Return to medium-low heat, cover and cook until
meat in thickest part is no longer pink about 10-12 minutes.
Stir remaining 1 tbsp.(tablespoon) vinegar into sauce. Pour fettuccine onto a warm deep platter; top and cover with chicken and sauce