1 whole roasting chicken (3 to 4 pounds)
Sea salt and freshly ground black pepper
4 tablespoons (1/2 stick) butter
1 tablespoon olive oil
1 cinnamon stick
2 whole star anise
1/2 cup roughly chopped cilantro stems
1 large lemon, cut into eighths
1 stalk lemongrass, 5 inches of white part only, chopped into 1/4-inch pieces
6 to 8 cloves garlic, peeled and smashed
1 (14- to 16-ounce) can coconut milk
3 cups torn greens (spinach, kale, chard, mizuna, etc.)
2 green onions, chopped into 1/4-inch pieces
Chopped cilantro, to garnish
Cooked rice, to serve