Wrap the beets individually in aluminum foil. Roast about 1 hour and 15 minutes or until fork tender. Remove beets from oven, unwrap and let cool 5 minutes before peeling. Slice the beets into eighths.
Remove the peel of the grapefruit with a sharp knife, cutting all the way down to the grapefruit flesh. Then cut the individual grapefruit segments out from their skin, using the supreme technique. Place the grapefruit segments in a bowl. Take the inner grapefruit remains and squeeze whatever juice you can out of it over the top of the grapefruit segments in the bowl.
Make the dressing by mixing together all the dressing ingredients along with all the juice that you can strain from the bowl of grapefruit.
Assemble the salad: Make a little heap of alfalfa in the middle of the plate. Scatter the cut beets around the plate. Pinch off pieces of the grapefruit segments and scatter them around the plate. Drizzle generously with dressing, top with a couple more grinds black pepper and serve.