Preheat the oven to 350°F.
Rinse the beet under cool water and then put the damp beet in a small roasting pan, cover, and roast for 45 to 60 minutes or until fork tender. Let the beet cool until you can handle it and then slip off the skins. They will come off easily. (If you wear latex gloves, your fingers won’t turn pink.) Cut the beets into thin slices, no more than 1/4-inch thick, and set aside.
Wash and peel the carrots. With a vegetable peeler, make lengthwise “ribbons” from the carrots by running the peeler along the length of the carrots. You need 16 to 20 carrot ribbons in all.
In a glass, ceramic, or other nonreactive mixing bowl, whisk together the avocado oil, lemon juice, salt and pepper.