Melt the butter (or heat the oil) in a saucepan over medium heat.
Add the onion and cook, stirring occasionally, until soft and translucent, 4 to 5 minutes. This is also where you'd add garlic or celery if you're using them — neither is in the base recipe, but both work well.
Toast the Rice
Add the rice and stir constantly for 2 to 3 minutes, until the grains turn opaque and smell faintly nutty.
This is the step that keeps grains separate instead of clumping — don't skip it.
Add the Hot Liquid
Pour in the warm stock — cold stock will throw off your timing — and bring to a gentle boil.
Season Early
Stir in the salt and pepper now, not at the end. The grains absorb seasoning as they cook.
Simmer & Cover
Reduce the heat to low, cover, and cook undisturbed for 15 to 18 minutes, until the liquid is fully absorbed. Resist lifting the lid or stirring.
Rest (don't skip this step)
Turn off the heat and let the pan sit, covered, for 5 minutes. This finishes the rice with trapped steam — don't skip it just because it looks done.
Fluff & Finish
Fluff with a fork, not a spoon, to keep the grains separate. Stir in the parsley just before serving.
Notes
You can also swap broth flavors or use brown rice (adjust cooking time).