1) Place greens in a bowl and toss with the vinegar and oil and season with salt and pepper. Transfer to a platter.
2) Arrange tomatoes over greens, sprinkle with salt, and drizzle with chive dressing.
3) Sprinkle blue cheese over top and garnish with a few fresh chives.
For the creamy chive dressing:
Combine all ingredients in a blender and blend until smooth.