Just fry off some onion, mushrooms(optional) and garlic (optional), add extra lean minced beef or quorn mince, fry until brown, throw in tinned toms or passata and a stock cube, any flavour will do to be honest. I usually use beef though. Add a teaspoon or so of oregano and basil or just one or other if you don't have both it doesn't matter. Simmer for as long as possible but at least half hour.
Also before you add the toms to it, grate in some veg to add sf food to it and bags of flavour, I always grate in courgette which practically disappears into the sauce, also carrot if I have it.
I also love it with baked beans thrown in!
Yum!