Serves 6.

2 pounds whole trimmed beets
2 sweet onions, unpeeled
1/2 cup vegetable oil
1/4 cup cider vinegar
2 tablespoons country-style mustard
2 tablespoons honey
1 tablespoon chopped fresh tarragon (or 1½ teaspoons dried tarragon)
Salt and freshly ground black pepper

Preheat oven to 400º. Rub beets with 1 tablespoon oil and wrap in aluminum foil. Wrap onions in aluminum foil, separately from beets. Roast beets and onions 45 minutes to 1 hour, or until soft when pricked with a fork. When cool enough to handle, peel the beets by rubbing off their skins. (If your beets are different sizes, remove the smaller ones as they are done and continue cooking the larger ones. Cut the beets into wedges.

Pull off and discard the onion skin, cut into quarters and then slice thickly crosswise. Whisk together the oil, vinegar, mustard, honey, tarragon, and salt and pepper and toss with beets and onions. Serve at room temperature for best flavor.