Preheat oven to 350 degrees F. Heat olive oil in a large, heavy skillet and saute chicken for 15 minutes until lightly browned. Transfer chicken to a large ovenproof casserole.
Saute garlic, green pepper, and onion over medium heat in remaining olive oil for 5 minutes. Add chicken broth to the skillet and bring to a boil over high heat. Stir in rice, paprika, oregano, black pepper, and saffron. Bring to a boil again.
Pour rice mixture over chicken pieces in casserole. Cover and bake for 40 minutes.
Remove casserole from oven. Add shrimp, clams, tomatoes, and peas. Cover and return to oven for 15 minutes.