- 1 1/2 tablespoons tarragon white-wine vinegar
- 1/4 teaspoon Dijon mustard
- 1/2 teaspoon salt
- 1/8 teaspoon black pepper
- 1/4 cup olive oil
- 2 medium beets (1 lb with greens; 14 oz without greens), stems trimmed to 2 inches
- 1 lb small new potatoes (about 1 inch in diameter) or fingerlings (1 to 1 1/2 inches long), scrubbed well
- 1 teaspoon olive oil
- 1/8 teaspoon salt
- 5 oz microgreens such as baby Bibb, red-leaf, and oak-leaf lettuces and baby arugula, or mesclun (about 10 cups)
- 4 cups baby spinach (3 oz)
- 1/3 cup lovage leaves, coarsely chopped
- 1/3 cup fresh chervil and/or dill leaves
- 1/3 cup fresh tarragon leaves
- 20 unsprayed organic nasturtium blossoms
Whisk together vinegar, mustard, salt, and pepper. Add oil in a slow stream, whisking until emulsified.
Roast beets and potatoes:
Put oven racks in upper and lower thirds of oven and preheat oven to 425°F.
Wrap beets individually in foil and roast on a baking sheet in upper third of oven until tender, 1 to 1 1/4 hours. Once beets have roasted for 30 minutes, toss potatoes with oil and salt in a small baking pan and roast in lower third of oven, shaking pan occasionally, until potatoes are tender, 25 to 30 minutes. Carefully unwrap beets and cool slightly, then slip off and discard skins.
Cut beets into 1/3-inch dice and put in a large salad bowl. Cut potatoes into 1/3-inch-thick slices and add to beets along with all greens and herbs. Add vinaigrette and toss gently to coat.
Sprinkle blossoms on top and serve immediately.