Preheat the oven to 400 degrees F. Wrap both beets in foil individually and place on a small baking sheet. Roast for 45 minutes. Then unwrap and cool a little. Slice the beets into thin rounds.
Meanwhile whisk all the ingredients for the garlic vinaigrette in a small bowl. Allow the dressing to sit for 15 minutes, then strain out the garlic chunks. Set aside.
Cut the tomatoes and mozzarella balls into thin rounds. Arrange the beets, tomatoes, mozzarella slices, and fresh basil leaves on a large platter. Drizzle with the garlic vinaigrette and sprinkle with cracked pepper before serving.