Place vermicelli noodles in a large heatproof bowl. Add hot water to cover. Let stand until noodles are tender, 10 to 15 minutes. Drain and set aside.

Meanwhile, toast chickpea flour in a medium saucepan over medium-low, stirring constantly, until flour is golden and fragrant, 3 to 5 minutes. Transfer toasted flour to a small bowl, and set aside. Wipe saucepan clean.

Heat oil in saucepan over medium. Add onion; cook, stirring often, until softened, 2 to 3 minutes. Add ginger, garlic, and Thai chile; cook, stirring often, until garlic is lightly browned, about 2 minutes. Add curry powder and turmeric; cook, stirring constantly, until fragrant and lightly toasted, about 1 minute. Stir in 2 tablespoons water, and scrape bottom of saucepan to release any browned bits. Add coconut milk, and bring to a boil over medium-high.

Meanwhile, stir remaining 1 tablespoon water into reserved toasted chickpea flour to form a slurry. Once coconut milk mixture comes to a boil, whisk in chickpea slurry. Cook, whisking constantly, until mixture thickens slightly, about 2 minutes. Reduce heat to medium-low, and simmer. Add shrimp; cook, stirring occasionally, until shrimp are just cooked through, 3 to 5 minutes.

Divide noodles evenly among serving bowls. Ladle curry mixture over noodles. Garnish with cilantro leaves, and serve with lime wedges.