To spiralize the beets, using gloves to prevent staining your hands, peel the beet and trim off the stem end then insert the thinner end into the round blade of the spiralizer, keeping it centered. Spiralize using the blade with the smallest triangles. Using scissors, cut the beet spirals into smaller 6-inch-long pieces so it's easier to eat.
Drain the mandarin oranges, reserving 2 tablespoons juice. In a mixing bowl, combine the juice, olive oil and red wine vinegar. Toss with the beets and let it sit for 15 minutes.
Divide in 2 plates, top with mandarin oranges and and mint.