*Wrap the beets in foil and roast for 40-60 minutes depending on their size. Roast until the beets can be easily pierced with a fork. Cool, then slip off the skins (C G: when I use fresh, in season beets I usually skip peeling the skins). Slice the beets in halves or quarters-again depending on their size.
*The beets can be roasted the day before then brought to room temperature.
Combine the beets, watercress or arugula and tomato slices on a salad plate. Drizzle the vinaigrette over the salad. Season with salt and pepper to taste.
While the beets are roasting prepare the vinaigrette by whisking the ingredients together in a small non-reactive bowl.
Arrange the beets, watercress/arugula and tomatoes on a salad plate. Drizzle the vinaigrette over the vegetables. Season with salt and cracked black pepper, to taste. I also garnished the salad with a little bit of lime zest.