In a large frypan heat oil over medium heat. Season chicken pieces with salt and pepper to taste and brown chicken in hot oil. Remove chicken from frypan. Set aside.
In same frypan saute onions and mushrooms until translucent. Return chicken to frypan and add the tomatoes, soup and wine. When liquids start to simmer add the green olives, black olives, capers and pepperoni. Cover frypan and let simmer for 30 minutes.
Preheat oven to 180 degrees C. Remove frypan cover, pour frypan mixture into a 20x30cm baking dish and bake in preheated oven for about 15 minutes, until chicken is tender and juices run clear.