Preheat oven to 450°F.
Toss sliced beets, 2 tablespoons oil, ½ teaspoon salt and ¼ teaspoon pepper in a large bowl. Arrange the beets in a single layer in a 9-by-13-inch metal baking pan. (Do not use a glass dish, which could shatter.) Cover with foil. Roast until tender, about 40 minutes. Remove and discard foil.
Combine ½ cup broth, 1 teaspoon orange zest, 2 tablespoons orange juice and 1 tablespoon honey in a liquid measuring cup; carefully pour into the pan. Continue roasting, uncovered, until the liquid thickens slightly and the beets are very soft, 12 to 15 minutes.
Drizzle with the remaining 1 tablespoon orange juice. Sprinkle with ¼ cup feta and 3 tablespoons pistachios. Drizzle with the remaining 1 tablespoon honey. Garnish with additional orange zest, if desired.
