Wrap beets in a single layer in aluminum foil and roast in a preheated 400°F (200°C) oven for 1 to 1½ hours, depending on their size, or until tender. Cool slightly. Rub off the skins and trim ends. Cut into wedges or slices.
In a small, heavy skillet, combine walnuts and sugar. Watching closely, cook on medium-high heat until sugar melts and coats walnuts. Add salt. Place on a baking sheet and cool.
For the dressing, combine vinegar, honey, salt and pepper. Whisk the oil into the mix.
Right before serving, toss greens with just enough dressing to coat. Divide greens between two plates, then top with beets, cheese and walnuts.