12 small golden or red baby beets (rinsed), roots and all but 1 inch of the stems trimmed off (4 ounces)
3-inch piece of peeled ginger root
1 tablespoon rice vinegar or white-wine vinegar
1/2 teaspoon sugar, or more to taste
Salt, to taste
3 tablespoons mild olive oil
4 ounces arugula leaves, tough stems removed as needed (about 4 cups loosely packed)
Preheat oven to 350 degrees.
Wrap the beets in heavy-duty aluminum foil, creating a loose but tightly sealed packet. Place on a rimmed baking sheet and bake for 30 to 45 minutes, until beets are tender (easily pierced with a sharp knife).
Carefully open packet and let beets sit until cool enough to handle. Use disposable food-safe gloves to rub or peel off skins, then trim off stem and root ends. Cut smaller beets in half and larger ones into quarters.
Use a vegetable peeler or small, sharp knife to shave about 16 slices from the ginger; slices should be as thin as possible. Grate remaining ginger to yield about 2 teaspoons.
Whisk together grated ginger, the vinegar, sugar and salt, to taste, in a small bowl. Slowly add the oil, whisking to combine. Taste and add salt, sugar or more ginger as needed.
Divide the arugula among individual plates. Scatter ginger slices and beets over arugula. Drizzle vinaigrette over each portion; serve immediately.
Makes 4 appetizer servings.