Add the chicken broth to a small pot and heat to warm it.
To a food processor or blender, add the tomatoes, onion, chili peppers, garlic, Mexican oregano, cumin, and salt and pepper to taste. Puree until smooth. Set aside.
Heat the oil in a large pan to medium heat and add the rice. Cook 6-7 minutes, stirring occasionally, until the rice is lightly toasted and golden brown.
Stir in the pureed tomatoes-chili mixture and cook 2-3 minutes to let the flavors bloom.
Stir in the chicken broth and optional extras (peas, corn). Bring the rice to a boil, then cover and reduce the heat to a simmer.
Cook, covered, for 15-20 minutes, or until the rice absorbs all of the liquid. Do not stir while cooking. If the rice gets too dry, add a few tablespoons of extra chicken broth or water.
Remove from heat and let sit for 5 minutes.
Fluff with a fork and garnish with chopped cilantro. Serve.