In a large skillet sauté onion and garlic in oil until tender over medium-low heat.
Reduce temperature to low and add rice and salt, stirring constantly for 3 minutes. This will add a nice toasted flavor to the rice.
Add stock and lime juice and bring mixture to a boil. Reduce and simmer for 10-15 minutes or until rice is tender, adding more liquid as needed.
Just before serving, stir in the zest and cilantro.