Where can I find Mega burger bun in Kestenholz?

Mega burger bun can also be found in these cities:

Balsthal Biberist Breitenbach Bubendorf Derendingen Egerkingen Egolzwil Erlinsbach Gerlafingen Herzogenbuchsee Huttwil Langendorf Langenthal Laufen Lostorf Murgenthal Oensingen Oftringen Olten Reiden Rothrist Schönenwerd Solothurn Utzenstorf Zell Zofingen Zuchwil

You can also find this in Kestenholz:

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