In a casserole put some olive oil (regular, not extra virgin). Fire your stove to a medium-low setting. Add some finely grated onion (I prefer the white variety). Once the onion becomes transparent (this is called “soffritto”) add a can of tomato sauce (I use the Hunt brand). Add also 1/2 can of sweet peas (drain them before use). Cover and cook, stirring often, for about 15-20 minutes. At the end, adjust salt.
In a stockpot add water (at least 1 quart per person) and fire the stove at the maximum power. When water boils add some salt (I use Kosher salt). Then add about 3.5 oz per person of Arborio Rice (please don’t use an inferior quality). Cook it until done (usually 16-18 minutes). Drain it and add the sauce previously prepared. Serve it immediately.