Pre-heat the oven to 200°C, 400°F, Gas Mark 6.
Combine the beef mince, breadcrumbs, egg and 1 tbs Oregano together, season and form into meatballs. Place on an ovenproof tray and cook in the oven for 20 minutes or until cooked through.
Heat the chopped tomatoes, tomato purée and remaining Oregano in a pan and stir in the meatballs.
Stir in the spaghetti, season to taste and garnish with more Oregano if desired.