Wrap beets in parchment paper. Microwave at HIGH until tender (about 7 minutes). Let stand 5 minutes. Cut into 1-inch pieces.
Section orange over a bowl; squeeze to juice. Place sections in a bowl. Add toasted walnut oil, minced shallots, Dijon mustard, pepper, and salt to juice; stir. Add beets, greens, and orange sections; toss. Top with pistachios and goat cheese.