Step 1Wash and trim the broccoli, then coarsely chop.
Step 2Heat the chicken broth in a large saucepan over medium heat to simmering. Add the chopped broccoli and simmer, covered, until tender, about 15 to 17 minutes.
Step 3Puree the mixture with an immersion blender right in the saucepan, or in a food processor in one or two batches, transferring each batch to a clean saucepan or warm tureen. Stir in the salt and pepper.
Step 4Spoon into serving bowls and finish with a squeeze of lemon juice and a sprinkle of Parmesan, if desired.