1 large sweet potato, cut into 1/2-inch cubes
2 1/2 teaspoons extra-virgin olive oil
Coarse salt and freshly ground pepper
2 beets, peeled and cut into 1/2-inch wedges, greens reserved and rinsed well
1 tablespoon white-wine vinegar
4 large eggs
1 leek, white and pale-green parts only, halved lengthwise, cut 1/4 inch thick, and rinsed well
1 cup cooked quinoa (from 1/4 cup dry)
3/4 teaspoon chopped fresh thyme