In a wok or soup pot over medium high heat, add cooking oil and swirl to coat. When hot, add in the garlic, ginger, red onion, chili pepper, lemongrass, kaffir and gently cook for about 2 minutes to release the aromas and flavors.
Step 2
Pour in the coconut milk and broth and let simmer for 15 minutes. Remove the lemongrass, kaffir (or the lemon/lime peel if using) and discard. Season broth with fish sauce and lime juice to taste.
Step 3
Add shrimp, salmon, vegetables and cilantro. Cook for 3-4 minutes or until the shrimp and salmon is cooked through.