Where can you buy very small blueberries like the ones in muffins mix?

You're likely referring to "dried blueberries" which are commonly found in muffin mixes and other baked goods.

Here's where you can buy them:

* Grocery stores: Most major grocery stores carry dried blueberries in the baking aisle.

* Bulk food stores: Stores like Costco, Sam's Club, and Trader Joe's often offer dried blueberries in bulk.

* Online retailers: Amazon, Walmart, and other online retailers sell dried blueberries in various sizes and brands.

* Specialty food stores: Some specialty food stores may carry premium or organic dried blueberries.

Important Note: When buying dried blueberries, look for ones that are plump, firm, and free of white powder. This indicates they are fresh and of good quality.