Gather all ingredients.
Combine ground beef, bell pepper, onion, and garlic in a large saucepan over medium-high heat; cook and stir until meat is browned and crumbly and vegetables are tender, 5 to 7 minutes. Drain grease.
Stir diced tomatoes, tomato sauce, and tomato paste into ground beef mixture; season with oregano, basil, salt, and black pepper. Simmer sauce for 1 hour, stirring occasionally.
Serve hot and enjoy!
