Classic Ranch with Broccoli Dippers

Name: Classic Ranch with Broccoli Dippers
Ingredients: Kosher salt and freshly ground pepper; 1 head broccoli, cut into long florets; or 2 bunches Broccolini; or a combination; 1/2 cup sour cream; 1/4 cup mayonnaise; 1/4 cup buttermilk; 2 tablespoons finely chopped fresh parsley; 2 tablespoons finely chopped fresh dill, or 1 teaspoon dried; 1 tablespoon minced fresh chives, plus more for serving; 1/4 teaspoon garlic powder; 1/2 teaspoon finely grated lemon zest and 1 teaspoon fresh juice, plus more zest for serving (optional)