The dressing is optional, since the beets are delicious without it, but it does add a tangy zest to this simple dish.
Bring water under steamer to a boil. Place washed, unpeeled beets in steamer basket. Cover and steam until tender when pierced with a paring knife, about 20 minutes. If you choose to use the dressing, mix it while beets are steaming. The dressing is made by whisking oil, lime juice, cumin together, then adding salt with pepper to taste. Set aside. Let beets cool. Peel off skins and cut in half. Toss with dressing mix until coated. Taste for seasoning. Serve warm or refrigerate and use for salads.
Wash but do not peel beets before cooking so the juices will not leach out during cooking.