Adapted from cooking.nytimes.com

1 pound (1 quart) potatoes
Beets from 1 bunch of beets
1 small onion, minced
2-3 hard boiled eggs, chopped
1 bulb fennel, raw, sliced into thin slivers
2 T sherry or red wine vinegar
1 T Dijion mustard
1/4 c plain yogurt
1/4 c olive oil
Salt and pepper to taste

Preheat oven to 400 degrees F. Trim the beets into 1 inch chunks, toss with olive oil and place in a roasting pan. Roast until tender. Remove and let cool

Boil the potatoes in salted water until just fork tender. Remove and run under cold water. When cool enough to handle, cut into 1 inch chunks.

Combine the beets, potatoes, eggs and fennel in a bowl that can accommodate all of them.

In another small bowl, combine the remaining ingredients and whisk until well combined. Drizzle the dressing over the potato and beet mixture. Taste and adjust for salt and pepper. Serve warm promptly, or allow to cool in the refrigerator before serving.