2. Meanwhile, prepare the dressing in a blender. Add the horseradish, red wine vinegar, honey and sour cream over low speed. Season with salt and pepper. Slowly add 1/4 cup of the canola oil until smooth and emulsified. Add half of the chives. Transfer to a bowl, cover and keep refrigerated until ready to serve.
3. Optional: Prepare the fried beet garnish. In a small saucepan, heat the canola oil for frying to 325°F. Add the julienne of beets, cooking until they just stop bubbling and are crisp, about 3 to 4 minutes. Transfer with a slotted spoon to paper towels to drain. Hold at room temperature.
4. When the roasted beets have cooled to room temperature, peel the skins from the beets by rubbing them with paper towels. Slice 4 of the beets very thinly.
5. Line your serving molds or a medium bowl with plastic wrap smoothly on the surface and excess on the edges to assist unmolding later. Layer the sliced beets, slightly overlapping each other, throughout the mold to create a thin even covering. Chill.
6. Cut the remaining 4 roasted, skinned beets into medium dice. Transfer to a bowl and combine with half of the dressing. Add the greens, tossing to combine while adding dressing as necessary to coat well. Transfer the salad into the molds and press to compact into desired shape.
7. Place the serving plate upside down over the bowl or mold. Invert the plate and bowl together so that the plate is upright and the salad is upside down. Gently and evenly pull on the plastic wrap to release the salad from the mold.
8. Drizzle the remaining dressing around the edges of the plate at the base of the salad. Sprinkle the remaining chives over the plate with black pepper. Top with optional fried beet julienne. Serve immediately.