Heat a 10-inch nonstick skillet over high heat. Add the oil and sauté the bean sprouts and mushrooms until tender, about 3 to 4 minutes. Season with the vegan fish sauce, then transfer the mixture to a bowl and set aside.

Whisk together the rice flour, all-purpose flour, turmeric, and salt in a medium bowl until well combined. Gradually pour in the water and coconut cream while stirring, then fold in the chopped scallion until the batter is smooth.

Wipe the skillet and return it to high heat. Once the pan is hot enough to smoke slightly, add a portion of the mushroom and sprout mixture, spreading it evenly across the surface.

Stir the batter to ensure the flour hasn't settled. Lift the pan from the heat and pour in enough batter to coat the bottom, quickly swirling the skillet in a circular motion to create a thin layer. If there are any gaps, patch them with a few extra drops of batter—it should sizzle immediately upon contact.

Return the skillet to medium heat and cover with a lid. Cook until the edges of the crepe begin to crisp and pull away from the pan, about 4 minutes.

Remove the lid and brush a little oil around the edges of the crepe. Continue cooking for another 2 minutes until the underside is browned and the crepe is rigid enough to handle.

Fold the crepe in half over the filling and slide it onto a plate. Repeat the process with the remaining vegetables and batter.

Prepare the dipping sauce by mixing the vegan fish sauce, sugar, and lime juice in a small bowl until the sugar is fully dissolved.

Serve the crepes warm alongside the lettuce leaves and fresh herbs for wrapping and dipping.