Peel beets and chop into both cubes and rounds. Place in a steamer and steam for 15 minutes or until they feel tender when pierced with a fork. Set aside and allow to cool. (note: I typically wear gloves when peeling beets so my hands don't turn bright red).
Combine all ingredients for dressing in a blender, blend until smooth. You can add more or less water depending on the thickness of dressing. I found 3/4 cup to be perfect.
Arrange lettuce, berries, and beets in a large bowl. Top with dressing. Serve