Creamy Carrot Soup with Lemon and Dill

Name: Creamy Carrot Soup with Lemon and Dill
Prep time: 30 min
Cook time: 30 min
Total time: 1 h
Cuisine: European
Ingredients: 2 pounds carrots (15 to 20 small to medium); 1 small yellow onion; 3 cloves garlic; 2 to 4 sprigs fresh dill; 1 medium lemon; 3 tablespoons unsalted butter; 1 1/2 teaspoons kosher salt; 1/4 teaspoon freshly ground black pepper, plus more for serving; 1 (32-ounce) carton low-sodium vegetable or chicken broth (4 cups); 1/2 cup heavy cream (optional)