Preheat the oven to 400ºF.
Wash and dry the beets and trim off the ends. Take a large sheet of aluminum foil, 12 by18, and double it over. Put the beets in the middle, drizzle with olive oil and season with the salt and pepper. Bring the sides of the foil up around the beets to make a pouch. Put in the hot oven and bake until the beets are tender, about 1 hour 20 minutes. Remove from the oven and let cool. When cool enough to handle, gently peel off the skin and slice into julienne pieces, about 2 inches long by 1/2-inch thick. Chill until ready to use.
Lightly toast the pine nuts in a small saute pan over medium-high heat for 3 to 4 minutes. Remove to a plate or small bowl and cool. Slice the goat cheese into 1/2-inch rounds and press the pine nuts onto both sides. Chill until service.
When ready to serve, lightly toss the baby greens and the spinach together in a large bowl and dress the edge of your serving bowl with 1/4 cup of the tarragon dressing. Toss the greens and then top with the beets and the goat cheese rounds. Drizzle with additional dressing and serve immediately.
In a small bowl or glass jar, combine all the ingredients, except the olive oil. Whisk until well h well combined, then slowly drizzle in the olive oil. This recipe works really well with a stick blender.