Preheat oven to 425°F.

In a large skillet, sauté the chicken with 1 tbsp oil over medium high heat for 5 minutes, or until chicken is thoroughly cooked and no longer pink inside. Set aside in a large mixing bowl.

In the same skillet, sauté the rice and vermicelli mixture in the remaining tbsp of vegetable oil, until golden brown.

Stir in 2 ½ cups water, and seasoning packet. Bring to a boil.

Cover. Reduce heat to low. Simmer for 15 to 20 minutes, or until rice is tender.

While rice is cooking, chop onions. Add 1/2 cup sour cream, green chiles and chopped onion to the mixing bowl containing the cooked chicken. Mix to blend.

Add cooked Rice-A-Roni^® to the chicken mixture and mix well.

In a separate bowl, whisk together eggs, milk, flour and chili powder. Stir in shredded cheese.

Place chicken and rice mixture in a round two-quart greased glass casserole dish. Pour the cheese and egg mixture evenly over the top of the chicken and rice.

Bake for 20 to 25 minutes uncovered, or until topping is puffed, crisp, and nicely browned.