Signature Microwavable Bowls – Costco Sale! by Rhonda February 7, 2023 2/3/21. © Frugal Hotspot *SALE UPDATE* 2/7/23. The colorful Signature Microwavable Bowls from Costco are a stylish way to serve food and then conveniently store the leftovers. These storage containers… 0 FacebookTwitterPinterestEmail