01 - Set the oven to 350°F (180°C) and allow it to come to temperature.
02 - Cook ramen noodles in boiling water, reducing package instructions by 2 minutes. Drain and hold aside.
03 - In a large skillet over medium heat, warm vegetable oil. Add onion, garlic, and ginger; cook until softened and aromatic, about 3 minutes.
04 - Add ground pork to the skillet, breaking it up with a spoon as it cooks. Continue until well browned.
05 - Stir in gochujang, crushed red pepper, crushed tomatoes, soy sauce, rice vinegar, and sugar. Season to taste. Simmer for 10 minutes until reduced and slightly thickened.
06 - In a mixing bowl, combine ricotta, egg, half the mozzarella, and half the parmesan until smooth.
07 - Spread a thin layer of meat sauce over the base of a 9x13-inch (22x30 cm) baking dish.
08 - Arrange approximately one pack of cooked ramen noodles as the first layer, trimming to fit as needed.
09 - Spread one-third of the ricotta mixture over the noodles, top with a third of the meat sauce. Repeat the layering process two more times, finishing with the remaining meat sauce on top.
10 - Evenly sprinkle the remaining mozzarella and parmesan cheese over the surface.
11 - Cover with foil and bake for 20 minutes. Remove foil and bake an additional 10–15 minutes until the cheese is bubbling and golden.
12 - Allow to stand for 10 minutes before slicing. Garnish with green onions if desired.