1 stalk of fresh lemongrass, tender inner bulb only, julienned
1 1/2 tablespoons Madras curry powder
One 14-ounce can unsweetened coconut milk
3 cups fish stock or bottled clam juice
1 tablespoon Asian fish sauce
1 tablespoon dark brown sugar
2 teaspoons Chinese chile-garlic sauce
Salt and freshly ground pepper
1 pound large red potatoes, peeled and cut into 2-inch chunks
2 pounds skinless red snapper fillets, cut into 2-inch chunks
2 tablespoons cilantro leaves
Steamed rice and lime wedges, for serving
In a large enameled cast-iron casserole or Dutch oven, heat the oil. Add the onion, garlic, ginger and lemongrass and cook over high heat, stirring, until golden, about 5 minutes. Add the curry powder and cook, stirring, until fragrant. Add the coconut milk, fish stock, fish sauce, brown sugar and chili-garlic sauce. Season with salt and pepper and bring to a boil.
Add the potatoes and simmer over low heat until tender, about 30 minutes. Add the fish and simmer, stirring occasionally, until just cooked through, 5 to 10 minutes longer. Stir in the cilantro. Serve the curry with rice and lime wedges.