- 3 tablespoons Asian fish sauce
- 2 stalks of fresh lemongrass, 4 inches of the tops reserved, tender inner cores only, thinly sliced crosswise
- 2 medium shallots, thinly sliced
- 2 garlic cloves, smashed
- 1 tablespoon sugar
- 1 tablespoon curry powder
- 2 tablespoons vegetable oil
- 1 medium onion, thinly sliced
- One 13 1/2-ounce can unsweetened coconut milk
- 4 canned plum tomatoes, drained and chopped
- 1 1/4 teaspoons turmeric
- 1/3 cup salted roasted peanuts, chopped
- Seasoning sachet made with 20 cilantro stems, 1 lime leaf, 1 red Thai chile and the reserved lemongrass tops, tied with string
- In a food processor, combine the fish sauce with the thinly sliced lemongrass and the shallots, garlic, sugar and curry powder; process to a fine paste.
- In a medium saucepan, heat the oil. Add the onion and cook over moderately low heat until softened and starting to brown, about 7 minutes. Stir in the coconut milk, tomatoes, turmeric and the spice paste and bring to a boil. Add the seasoning sachet and simmer over low heat, stirring occasionally, until the sauce coats the back of a spoon, about 15 minutes. Let cool slightly, then pull out and discard the sachet. Transfer the contents of the saucepan to a blender. Add the peanuts and blend to a puree. Season with salt.