Prepare your berries by washing them thoroughly and patting them dry. Chop the tops of your strawberries off and halve them if they're large to make things easier.
Add the berries to a blender, and add your apple juice. Add 200ml and then blitz, and add more as you go to get your desired thickness.
Once blitzed and smooth, pass through a sieve if you don't want lumps, but I just pour it into my Kilner Jars and drank it!
Notes
I used the cute Kilner jars in the photos, and the recipe comfortably filled three of them. Obviously, the more juice you add, the more in volume you'll get.
I used fresh berries and not frozen, so it was a lovely smoothie. However, you can easily have an amazing chilled smoothie by using frozen berries! You might just need to add more liquid.
You can add water instead of apple juice if you wish, or any other liquid.
You can use any berry in reality, but obviously the taste will vary. You can even just use 200g of strawberries, and 200g of raspberries etc. Or all raspberries!