Peel beets and slice 1/8-inch thick. In a small bowl, combine salt, rosemary and garlic powder.
Gently toss beets with the olive oil and salt mixture. Line cooking sheet with parchment paper and lightly mist with nonstick cooking spray. Arrange beets on the sheet so they are not overlapping or touching.
Bake 15 minutes, turn over and continue baking until golden, approximately 10-15 minutes (being careful not to burn). Allow to cool to room temperature and store in an airtight container.
Squeeze as much water from the shredded cucumber as possible. Combine cucumber, Greek yogurt, garlic, dill, olive oil, and salt in bowl. Stir until combined and refrigerate until ready to serve.