Heat olive oil in a skillet or Dutch pot over medium-high heat. Add onion and green pepper and sauté for about 3-5 minutes.
Add garlic and stir for about 1 minute.
Add shredded cabbage and stir. Cook for about about 3-5 minutes, stirring often until softened.
Add corned beef, Roma tomatoes, and thyme and stir. Add ketchup and scotch bonnet pepper sauce and stir. Reduce heat and cook on medium for about 3-5 minutes, until the corned beef is heated through. Remove from heat.
Serve with white rice, bread, or on its own.