Serves 6 people
2 bunches medium beets, preferably a combination of red and golden beets, trimmed (not peeled) and scrubbed
1 tablespoon olive oil
½ cup shelled pistachios, preferably Sicilian, plus (optional) chopped pistachios for garnish
About ¼ cup warm water
2 tablespoons pistachio oil
2 tablespoons Red Wine Vinaigrette
Maldon or other flaky sea salt and coarsely ground black pepper
Preheat the oven to 400 degrees F.
Toss the beets with the olive oil and a light sprinkling of Kosher salt in a medium bowl. Spread the beets out in a baking pan and roast until tender, about 50-60 minutes. Remove from oven and let cool slightly.
Meanwhile, pulse the pistachios in a food processor until fairly finely ground. Add 3 tablespoons water and pulse to incorporate it. Add the oil and pulse until smooth, adding up to 1 ½ more tablespoons water if necessary. (The pistachio butter can be made ahead and refrigerated for up to 3 days; bring to room temperature before serving.)
Rub the skins off the beets with a paper towel. Cut into 1-inch chunks and transfer to a serving bowl. Toss the beets with the vinaigrette and let stand for at least 10 minutes, for up to 1 hour, before serving. (The beets can be refrigerated for up to 3 days; bring to room temperature before serving.)
Transfer the beets to a platter or plates and garnish with the remaining pistachios. Spoon the pistachio butter alongside and serve.