Had all the ingredients for this, buttermilk & blueberries in the freezer so thawed the buttermilk but left the blueberries frozen.
You are supposed to pour the blueberry mixture into a glass and top it with the buttermilk mixture but my blueberries didn't make a liquid so I added most of the buttermilk to them, blitzed again then just poured a small amount of the buttermilk mixture on top.
Absolutely delicious and I drank both glasses for breakfast
Linked JD