1. Preheat your oven to 350°F (175°C). This gentle heat will allow all the flavours to meld without drying out the rice.
2. In a large oven-safe skillet or casserole dish, heat the olive oil over medium heat. Add the sliced onions and a pinch of salt. Cook slowly, stirring occasionally, until the onions turn a deep golden brown and are beautifully caramelised — this usually takes about 25-30 minutes. Trust me, the patience here pays off in pure flavour.
3. While the onions caramelise, in a separate pan, brown the ground beef over medium-high heat. Break it up as it cooks until no pink remains, about 6-8 minutes. Drain excess fat if necessary.
4. Add the minced garlic to the caramelised onions and cook for another minute until fragrant.
5. Stir in the browned beef, dried thyme, Worcestershire sauce, salt, and pepper. Mix everything well so the beef soaks up those sweet onion flavours.
6. Sprinkle the rinsed rice evenly over the beef and onion mixture. Pour the beef broth gently over the top — don’t stir once the broth is added! This helps the rice cook evenly in the oven.
7. Cover the skillet or casserole dish tightly with a lid or foil. Bake in the preheated oven for 35-40 minutes, or until the rice is tender and has absorbed all the liquid.
8. If using cheese, remove the casserole from the oven, sprinkle the shredded Gruyère evenly on top, and return it uncovered for another 5-7 minutes, or until the cheese is melted and golden.
9. Let the casserole rest for 5 minutes before serving. Garnish with fresh parsley for a pop of colour and freshness.

One of my little kitchen secrets, passed down from my mum, is to resist the urge to stir the rice once it’s in the oven. Stirring can release starch and make the rice gummy, which is the last thing you want in a comforting casserole like this.