Bring a large pot of lightly salted water to a boil. Place pasta in the pot, cook for 8 to 10 minutes until al dente and drain.
In a large frypan over medium heat, mix the beef, onion and garlic then cook until beef is evenly brown.
In a blender or food processor, liquefy the tomatoes. Pour into the frypan with the beef. Mix in beef stock cubes, sugar, garlic salt and pepper. Cover and simmer 10 minutes, stirring occasionally until stock cubes have dissolved. Stir in the pasta until evenly coated with the sauce to serve.