In a medium sized salad bowl, using your microplane grater (or the smallest holes of a cheese grater) grate fresh ginger directly into bowl, about one teaspoon. Grate beets and apples, add them to the bowl with the ginger, and toss until ginger is evenly distributed. Add sherry vinegar, salt, and pepper to bowl and toss to coat evenly. Add olive oil, stir to combine. Taste and adjust seasonings. Serve immediately or keep refrigerated.