Whisk together the hoisin sauce, soy sauce, brown sugar, sesame oil, cornstarch, garlic powder and ginger until well blended. Set aside. Place a nonstick skillet over medium-high heat. Add the broccoli slaw and water and cook, stirring frequently until tender, about 6 minutes. Add the shrimp and the sauce (rewhisk if necessary) and stir constantly until heated through and thickened, 2 to 3 minutes. Divide the shrimp mixture evenly among the lettuce leaves, top with peanuts, roll up, and serve.
