Spring Minestrone With Chicken Meatballs

Name: Spring Minestrone With Chicken Meatballs
Ingredients: 6 ounces ground chicken (about 3/4 cup); 1/2 cup fresh breadcrumbs; 6 tablespoons finely grated Parmesan, divided, plus more for garnish; 4 garlic cloves, 2 minced, 2 thinly sliced; 2 tablespoons chopped fresh chives; 1 large egg, whisked to blend; Kosher salt, freshly ground pepper; 2 tablespoons extra-virgin olive oil; 1 leek, white and pale-green parts only, sliced into 1/4-inch rounds; 5 cups low-salt chicken broth; 3/4 cup ditalini or other small pasta; 1 cup 1/2-inch rounds peeled carrots; 1 cup (packed) baby spinach; Chopped fresh basil