How to Make It
In a small bowl, soak the raisins in the hot water until plumped, about 15 minutes.
Meanwhile, in a small skillet, heat the vegetable oil. Add the shallots and garlic and cook over moderate heat, stirring constantly, until browned, about 5 minutes. Add the Thai chile and cook 1 minute longer.
In a large saucepan, mix the sugar with the molasses and cook over moderate heat, stirring frequently, until the sugar is melted and lightly caramelized, about 8 minutes. Stir in the tomato paste, tamarind concentrate, anchovy, chipotle, thyme and orange zest and cook until a thick paste forms, about 1 minute. Stir in the vinegar, star anise, cloves and the shallot mixture. Add the raisins with their soaking liquid along with the room-temperature water. Bring the sauce to a simmer and cook over low heat, stirring occasionally, until the sauce has reduced slightly, about 10 minutes. Let cool slightly. Transfer to a blender and puree until very smooth. Season with salt and let cool completely before serving.
Tamarind concentrate, the strained, concentrated pulp from tamarind pods, is available at Indian markets and specialty-food shops.