Preheat the oven to 350 degrees F.

Place a 2-quart, ovenproof saucepan over medium-high heat and add the olive oil. Once the oil is hot, add the onions and cook, stirring often, until they are translucent and begin to soften, about 4 to 5 minutes. Add the garlic to the pan and saute for 30 seconds. Add the rice to the pan and saute (being sure to stir the rice and coat it with the oil), until toasted, about 4 to 5 minutes. Season the rice with the salt and white pepper. Add the chicken stock to the pan and cook, stirring occasionally, until the water comes to a boil. Cover the pan with a lid and place the saucepan in the oven. Cook the rice for 30 minutes, remove from the oven and let stand for 5 minutes. Remove the lid, and add the green onions to the pan and toss with a fork to combine.