Lemongrass And Coconut Curry With Summer Vegetables

Name: Lemongrass And Coconut Curry With Summer Vegetables
Ingredients: 1 tablespoon vegetable oil; 2 tablespoons (or more) Thai curry paste; 5 scallions, thinly sliced, white and pale-green parts and dark-green parts divided; 3 garlic cloves, thinly sliced; 1 1-inch piece peeled ginger, thinly sliced; 6 cups mixed 1/4-inch-thick sliced vegetables (such as Japanese eggplant, long beans, summer squash, and bell peppers); 2 lemongrass stalks, bottom third only, tough outer layer removed, bruised with the back of a knife or a rolling pin; 2 cups (or more) chicken broth or vegetable stock; 1 13 1/2-oz. can light unsweetened coconut milk; 2 skinless, boneless chicken breasts, cut into small cubes (optional); 2 sprigs basil plus leaves for garnish; 1 tablespoon (or more) fish sauce (such as nam pla or nuoc nam; optional); Kosher salt; Steamed rice (optional); Lime wedges (optional)