Preheat oven to 350 degrees. Add butter to a small mixing bowl then add honey and pecans. Stir to coat then spread pecans out on a silpat or parchment paper-lined baking sheet and bake for 5-6 minutes, or until golden brown and fragrant (watch carefully so they don't burn). Sprinkle lightly with salt then set aside and let cool completely — can be made ahead of time.
For the Berry-Balsamic Vinaigrette:
Add blackberries and sugar to a food processor or blender then process or blend until berries are crushed. Let sit for a minute then add remaining ingredients and process or blend until smooth. Set aside — can be made ahead of time.
Divide lettuce between plates then top with blackberries, blue cheese crumbles, and honey-roasted pecans. Drizzle with berry-balsamic vinaigrette then serve.