You may find other Costco muffin flavors for 2022, depending on when and where you visit. ...  Costco Muffin Flavors Blueberry Muffins* Double Chocolate Muffins. Corn Muffins* Pumpkin Streusel Muffins* Chocolate Chip Muffins. Almond Poppy Muffins. Banana Chocolate Chunks Muffins. Vanilla Chocolate Chunk Muffins. More items... Oct 17, 2022