ALL ITEMS › sourdough bread | Thunderbird Bakery Image 1 of 6 Image 2 of 6 Image 3 of 6 Image 4 of 6 Image 5 of 6 Image 6 of 6 sourdough bread | Thunderbird Bakery $7.00 sliced loafNaturally leavened sourdough with a mild, tangy flavor produced by Thunderbird Bakery in Oshkosh, WI. Add To Cart Added! sliced loafNaturally leavened sourdough with a mild, tangy flavor produced by Thunderbird Bakery in Oshkosh, WI.