Cook the macaroni. Break the macaroni in half and add to a pot of salted boiling water. Cook until al dente, about 7 to 9 minutes. Drain and set aside.

Sauté the vegetables. While the macaroni cooks, heat a large nonstick pan over medium heat. Add the onion, pimento peppers, and bell pepper. Sauté for 2 to 3 minutes, until they begin to soften.

Cook the corned beef. Add the corned beef and break it apart with a spoon as it softens. Cook for about 5 minutes.

Add the sauce and vegetables. Stir in the tomatoes, ketchup, hoisin sauce, corn, all-purpose seasoning, and pepper sauce. Cook until everything is heated through and well combined. Keep the mixture fairly saucy rather than cooking it down until dry.

Combine. Add half of the drained macaroni and mix well. Add the remaining macaroni and toss again until the corned beef, vegetables, and sauce are evenly distributed.

Finish and serve. Taste and adjust with salt, black pepper, and additional pepper sauce if needed. Stir in the scallions and serve warm.