Where can I find Power bar in Koppigen?

Power bar can also be found in these cities:

Bern Biberist Bremgarten bei Bern Burgdorf Derendingen Gerlafingen Grenchen Hasle bei Burgdorf Herzogenbuchsee Hinterkappelen Huttwil Ittigen Kirchberg Langendorf Langenthal Moutier Murgenthal Münchenbuchsee Oensingen Ostermundigen Solothurn Utzenstorf Zollikofen Zuchwil

You can also find this in Koppigen:

Desserts Dessert Baking Mixes Cake Glaze Peanut Butter Ice Cream Rice Dishes Vegetable Juices Instant Iced Coffee Cheese Roll Canned Fish