- 6 medium beets, trimmed
- 1 large English hothouse cucumber, unpeeled, cut into 1/4-inch-thick rounds
- 1/2 sweet onion (such as Maui or Vidalia), halved lengthwise, thinly sliced
- 4 teaspoons honey
- 4 teaspoons apple cider vinegar
- 1 1/2 teaspoons Dijon mustard
- 1/3 cup corn oil
- Preheat oven to 400°F. Wrap each beet in foil, enclosing completely. Place on rack in oven and bake until beets are tender when pierced with fork, about 1 hour 30 minutes. Cool in foil. Peel beets, then cut each into 6 slices.
- Arrange beets, slightly overlapping, on half of large platter. Arrange cucumber slices on other half. Scatter onion in center. (Can be made 4 hours ahead; chill.)
- Whisk honey, vinegar, and mustard in small bowl to blend. Gradually whisk in oil. Season with salt and pepper. Drizzle over vegetables.