Preheat your oven to 375°F. Grab a 9 x 13-inch glass or ceramic baking dish.
In a blender or food processor, combine onion, tomatoes, garlic, jalapeño, and tomato paste. Blend until a smoothish sauce is formed, about 30 seconds. You should get about 2 cups of sauce. Pour it into a medium saucepan, mix in the broth, and let it come to a simmer over medium heat.
While the tomato mixture is heating up, spread the rice over the bottom of the baking dish and drizzle the oil and salt over the top.
When the broth mixture is at a gentle simmer, pour it over the rice, stir it up, cover tightly with foil, and put it in the oven. Let it bake for 1 hour without checking to avoid letting out steam.
After 1 hour, pull out the baking dish and fluff the rice around with a fork. If the rice isn’t fully cooked, add another 0.25 cup broth or water, cover, and bake for another 10 minutes. Fold in the corn, peas, lime juice, and cilantro. Mix well and add a pinch more salt if needed. Serve right away.
Modifications
Fresh or thawed frozen ingredients can be used; it’s not a deal-breaker here.