Heat oil in large wide skillet or sauté pan over medium-high; cook rice 5-7 minutes, stirring frequently, until golden brown and fragrant.
Cook onion with rice 3-4 minutes until softened; stir in garlic and cook 1 minute until fragrant.
Stir in tomato sauce, broth, cumin, chili powder, salt, and pepper until combined.
Boil; reduce heat to low, cover tightly, and simmer 20 minutes without lifting lid.
Remove from heat; stand covered 5 minutes. Fluff with fork, stir in optional peas, and top with cilantro.