Line 2 trays with plastic wrap and put them in the freezer until the trays are frozen.
Stir the yogurt to make sure it is smooth. Drop 6 blueberries at a time onto the top of the yogurt and using a fork coat them in the yogurt.
Tap the fork lightly on the side of the container to take off any excess yogurt and tip the blueberry onto the pre-frozen tray.
After 1 cup of blueberries have been dipped return the tray to the freezer and start using the second tray.
Leave for an hour to completely freeze.
Loosen the blueberries with a knife and sprinkle the raspberry powder over the blueberries using a sieve. Tip them into a serving bowl and re-coat with raspberry powder if needed.
