With their magnificient color, delicious flavor, and vitamin richness, beets are one of my favorite vegetables. In the summer I serve this soup at room temperature; in the winter I like it hot.
Nash uses thin gloves when she works with beets, as this avoids staining her fingers with beet juice, which can be hard to remove.
Peel and slice the beets.*
Heat the oil in a medium saucepan. Add the onion, garlic, and apple and sauté for 5 minutes. Add the beets and broth. Bring to boil over high heat. Lower the heat and cook, covered, until the beets are tender, about 30 minutes. Cool for a little.
While the soup is cooking, wrap the reserved beet tightly in foil. Bake in a toaster over at 400 degrees until just tender when pierced with the tip of a paring knife, about 30 minutes. Cool, slip the skin off, and grate.
Purée the soup until very smooth. Season to taste with vinegar, sugar, salt, and pepper.
To serve, garnish with the grated beet.