Fill a large pot with lightly salted water and bring to a rolling boil over high heat. Once water is boiling, stir in macaroni, and return to a boil. Cook pasta uncovered, occasionally stirring, until pasta has cooked through, but is still firm to the bite, about 8 minutes. Drain well in a colander set in the sink.

Heat olive oil in a large pot over medium heat, and cook onion and garlic until onion is soft, about 5 minutes; stir in green pepper, and cook until tender, about 8 more minutes.

Mash corned beef into the pot, and simmer until hot. Mix in tomato soup, ketchup, cooked macaroni, salt, and black pepper; stir to combine, and bring mixture to a simmer over medium-low heat.