Tom Kha Tofu (Thai Coconut Soup)

Ingredients (for 3 servings)

• 1 tbsp — oil • 1 medium onion, sliced • 3 garlic cloves, minced • 1 tbsp fresh ginger, grated • 1–2 stalks lemongrass, bruised and cut into large pieces (optional but recommended) • 4 cups vegetable broth • 1 can light coconut milk • 200–250 g firm tofu, cubed • 1 cup mushrooms, sliced • 1–2 tbsp soy sauce or tamari • 1–2 tbsp lime juice (plus more to taste) • 1 tsp maple syrup or sugar (optional, for balance) • 1/2 tsp salt, or to taste • 1–2 kaffir lime leaves • 1–2 Thai chilies or chili flakes • 2–3 green onions, sliced • 1/4 cup fresh cilantro, chopped