Preheat the oven to 350 degrees F (175 degrees C). Cut wonton wrappers into 1/4-inch strips. Transfer cut wonton wrappers to a baking pan and toss with oil. Spread out evenly. Bake in the preheated oven until browned, about 12 minutes. Let cool and reserve. Combine cabbage, carrot, bell pepper, green onions, and garlic for the bowl. Set aside. Mix soy sauce, rice vinegar, sake, sesame oil, sugar, ginger, cayenne, pepper, ketchup, and cornstarch together for sauce in a bowl and reserve. Add pork to a large skillet set over medium-high heat. Brown the meat well, while breaking up into small crumbles as it cooks, 5 to 7 minutes. Add the vegetable mixture and toss with the meat to combine. Cook, stirring, just until the veggies start to soften, about 2 minutes. Stir in the sauce and toss everything to combine. Cook and stir until the sauce has coated everything evenly, and the vegetables are cooked to desired doneness, 1 to 2 minutes more. Serve in a bowl with crispy wonton strips on top.