Bring a pot of water to a boil. Add green beans and simmer until beans are cooked through. Run tap water over the beans to cool down. Drain and set aside.

In a small bowl, add peanut butter, light soy sauce and vinegar. Mix well and set aside.

To cook chili oil (*see footnote), add chili flakes, peppercorn, star anise and sesame seeds into a small bowl. Place the bowl on a heat resistant mat (or cutting board). Heat oil in a wok (or a skillet) until hot, when the oil just starts to smoke. Turn off heat immediately. Carefully use a ladle to transfer oil to the bowl of mixed spices. The oil will bubble for a few seconds and cook the spices. When the the oil stops bubbling, immediately use a spoon to stir gently, to mix everything well.

Place the green beans on a plate and top with peanut sauce and garlic. Gradually add spicy oil, 1 teaspoon at a time, and mix everything well. Taste the salad to see whether it's spicy to your liking. You can add more chili oil if you prefer a spicier dish.

Serve at room temperature.