Preheat oven to 350 degrees. In a medium ovenproof saucepan, heat olive oil. Add onion and mustard seed, and saute until onion is just wilted, about 2 minutes. Add bell pepper. Continue to cook until vegetables become soft, 3 to 5 minutes.Advertisement
Add rice and salt. Stir well to combine. Add chicken stock, and bring to a boil. Cover tightly with a lid, and place in the oven. Cook until liquid is absorbed and rice is al dente, about 17 minutes.
Remove from oven. Fluff with a fork, and stir in snipped chives. Serve immediately.