In a bowl, combine the ancho chili powder, light brown sugar, chile de arbol, cinnamon, and cumin, and set aside. In a medium size bowl, place the shrimp. Salt and pepper the shrimp aggressively. Then, sprinkle the shrimp with the spice mixture on both sides. Place the shrimp on a baking sheet and drizzle with oil. Roast for 4 to 5 minutes, or until just cooked through.
Place the arugula in a bowl, drizzle with some of the Smoked Chile Vinaigrette and season with salt and pepper, to taste. Divide the seasoned arugula among 4 plates. Place 6 shrimp around each plate. Drizzle with more of the vinaigrette and chopped cilantro.
Smoked Chile Vinaigrette:
Combine vinegar, chipotle and cilantro in a blender and blend until smooth. With the motor running, slowly add the oil until emulsified. Season with honey, salt, and pepper, to taste.