Beet, Arugula, and Shanklish Salad with Kumquat and Orange Dressing

We take our sweet, tender Mediterranean beets for granted. We boil them in water, and they are perfectly succulent with any dressing, even eaten plain, skin removed. When I first tasted roast beets in the United States, I realized that the strain of sweet beets that thrive in our garden is very different from the one cultivated here, which lacks the fruitlike flavor of Mediterranean beets. But I was determined to get my kind of tender sweetness out of common American beets, and here is my r