In a 12-inch ovenproof skillet, cook chicken in hot oil over medium heat about 10 minutes or until chicken is lightly browned, turning to brown evenly. Remove chicken.
Add onion and garlic to skillet. Cook about 5 minutes or until onion is tender. Stir in rice. Cook and stir until rice is light brown.
Drain clams, reserving liquid; set aside. Stir cumin, salt, pepper, and saffron into skillet; add undrained stewed tomatoes, chicken broth, water, and reserved clam liquid. Bring to boiling. Top with chicken pieces. Cover tightly and bake in a 400 degree F. oven for 15 minutes.
Stir in reserved clams, peas, shrimp, and olives. Cover and bake about 15 minutes more or until chicken is tender and no longer pink and shrimp turn opaque. Let stand 5 minutes before serving. Garnish with parsley, if desired. Makes 6 servings.