Fry the onions for a few minutes in a tiny bit of oil, then add garlic. After 30 seconds add the mince and fry until there is no longer any pink, breaking up any chunks of mince.
Drain away any fat from the mince, sprinkle over the flour and combine, add beef stock, passata, caster sugar, oregano, mixed herbs, Worcester sauce and mix together and season, turn down the heat and simmer for around 10-15mins. If the mixture is too thick, add a bit more water.
Whilst the mince is simmering, boil the spaghetti according to the packets instructions.
Drain the spaghetti and divide between warmed pasta bowls. Spoon the bolognese mixture on top, sprinkle with freshly grated cheese and serve immediately with crunchy garlic bread.