1. In a large saucepan, heat the oil over moderately low heat. Add the onion and cook, stirring occasionally, until it is translucent, about 5 minutes. Add the garlic, ginger, five-spice powder, cumin, cayenne, turmeric, and 1/2 teaspoon of the salt. Stir until fragrant, about 1 minute. Whisk in the broth and then the coconut milk; bring to a simmer. Stir in the potatoes, cover, and cook over low heat until they are almost tender, about 12 minutes.
2. Add the chicken to the sauce, cover, and simmer for 5 minutes. Stir in the peanuts, tomatoes, cilantro, and the remaining 1/2 teaspoon salt. Turn the heat off, cover, and let steam until the chicken is just done, about 2 minutes longer.
Menu Suggestion: For this curry, steamed white rice is the only accompaniment you need.
Wine Recommendation: For this bold curry, bursting with heat, spice, and sweetness, a fresh, aromatic white that won't get pushed around--a chenin blanc from the Loire Valley in France or from California, for example, or a sauvignon blanc from New Zealand--is a good match.