My mum used to make this a lot, and still does - I don't know if this is the exact recipe but this is how I make it, retaining the key elements of tomatoey, ricey, veryveryvery garlicky.
We always used to have it for dinner with either a bacon, fishfinger, or - God help me - a TURKEY BURGER sandwich (the Bernard Matthews ones, from the freezer, oh man I'm going to have to see if they still do them!)
So the basic principle is this. You want it to be as tomatoey and garlicky as you can stand it. That's all you need to know. Some super awesome stock will make this amazing but you know what, an instant will do fine too. This was a weekly freezer staple in our house growing up and I'm sure my mum wasn't off roasting chickens to make stock all the time - both my parents worked and she would just whip this out of the freezer and reheat it (so yes, it freezes very successfully and I often make a huge batch and take it for lunch to work. It guarantees nobody will sit by me all week).
Makes one large pot to consume as you see fit :)
LOTS of garlic - and I mean obscene amounts
Lots of passata, or canned tomatoes in juice - probably about 2-3 400g cans or a large (750ml) jar of passata and an extra can for luck
tomato puree - again, you're looking at about 2 tablespoonfuls
dried parsley (a pinch)
2 tbsp finely grated parmesan
salt and black pepper
Start by sauteeing the onions in a blob of butter, very gently - you want them completely soft and golden but not browned. Also, they need to be very finely chopped as this is a soup you don't blend. Add the garlic when they start to soften and allow that to cook down with them.
Then, add the tomatoes, the tomato puree, the parmesan, parsley, salt, and black pepper, bring it up to the boil and then reduce down to a low, low simmer, cover and leave it for about half an hour.
Add the rice and about 750ml chicken stock, cover again and leave it to simmer. The rice needs to go BEYOND cooked and into the mushy, thick stage. Just keep checking in on it and see that it meets your idea of liquid or thick enough - it's your soup, innit.
Welcome additions if you want to fancypants it; some chorizo or pancetta right at the start with the onions, some Italian herb seasoning, well...you name it. Chili, whatever. But I like this as is with the TURKEY BURGER SANDWICH. Actually, a good cheese one is a pleasure too.