In a blender combine the poblano, cilantro, onion, jalapeno (if using), salt, pepper and ½ cup water. Blend until smooth. In a saucepan heat oil over medium-high heat. Add the rice and cook stirring, until the rice is light, golden brown and has absorbed most of the oil, about 5-8 minutes. Add the puree, stir and continue cooking until mixture thickens slightly, about 2 minutes. Add 1 ¾ cups water, stir and bring to a gentle boil. Cover; reduce heat to low and cook until all liquid has been absorbed, about 10-15 minutes. Do not stir rice during this cooking time. Once all liquid is absorbed remove from heat, let stand covered for an additional 5 minutes. When ready to serve fluff rice, garnish with cilantro and serve with lime wedges.