In a large bowl, combine the rice flour, cornstarch, turmeric powder, and salt.
Whisk in the coconut milk and water until smooth.
Stir in the thinly sliced green onions.
Let the batter rest for at least 30 minutes.
In a small bowl, combine the fish sauce, lime juice, water, sugar, minced garlic, and sliced red chili.
Stir until the sugar is dissolved. Set aside.
In a large skillet, heat 1 tablespoon of vegetable oil over medium-high heat.
Add the thinly sliced pork and cook until browned, about 3-4 minutes.
Add the shrimp and cook until pink and opaque, about 2-3 minutes.
Remove the pork and shrimp from the skillet and set aside.
In the same skillet, add the remaining 1 tablespoon of vegetable oil.
Sauté the thinly sliced onion and mushrooms (if using) until softened, about 3-4 minutes.
Remove from heat and set aside.
Heat a non-stick skillet over medium-high heat.
Lightly grease the skillet with a small amount of vegetable oil.
Pour a ladleful of batter into the skillet, swirling to cover the bottom with a thin layer.
Cook for 2-3 minutes, until the edges start to crisp and lift from the skillet.
Add a portion of the pork, shrimp, sautéed onion, mushrooms (if using), and a handful of bean sprouts to one side of the crepe.
Fold the other side of the crepe over the filling and cook for another 1-2 minutes, until the crepe is crispy and the filling is heated through.
Transfer the cooked crepe to a plate and repeat with the remaining batter and filling.
Enjoy your meal!