01 -  Set the oven to 350°F (180°C) and allow to preheat completely. 
 02 -  Boil ramen noodles for 2 minutes less than package instruction; drain thoroughly and set aside. 
 03 -  Heat vegetable oil in a large skillet over medium heat. Sauté onion, garlic, and grated ginger until translucent and aromatic, about 3 minutes. 
 04 -  Add ground pork to the skillet. Cook, breaking up the meat, until evenly browned. 
 05 -  Incorporate gochujang, red pepper flakes, crushed tomatoes, soy sauce, rice vinegar, and sugar. Season with salt and pepper. Simmer for 10 minutes until thickened slightly. 
 06 -  In a mixing bowl, blend together ricotta, egg, half the mozzarella, and half the parmesan until smooth. 
 07 -  Spread a thin layer of meat sauce on the bottom of a 9x13-inch baking dish. 
 08 -  Arrange one pack of cooked ramen noodles to cover the meat sauce evenly. 
 09 -  Spread one third of the ricotta mixture over noodles. Top with one third of the meat sauce. 
 10 -  Repeat layering noodles, cheese mixture, and meat sauce twice more, ending with meat sauce on top. 
 11 -  Sprinkle remaining mozzarella and parmesan over the assembled dish. 
 12 -  Cover baking dish tightly with foil. Bake for 20 minutes. 
 13 -  Remove foil and continue baking for 10–15 minutes, until the cheese is bubbling and lightly golden. 
 14 -  Let stand for 10 minutes prior to slicing. Garnish with sliced green onions if desired.