Sauté the aromatics: Heat the vegetable oil in a large, deep skillet over medium-high heat. Add the onion and garlic and cook for about 3 minutes, stirring occasionally, until softened and fragrant.
Brown the beef: Add the ground beef, breaking it into crumbles as it cooks. Cook until browned and no pink remains.
Build the flavor: Stir in the cilantro stems, chili powder, cumin, paprika, oregano, garlic powder, onion powder, kosher salt, black pepper, cayenne pepper and tomato paste. Cook for 1 minute, stirring, to toast the spices.
Add the rice and vegetables: Stir in the uncooked rice, black beans, corn, cherry tomatoes, salsa and chicken broth, scraping up any browned bits from the bottom of the skillet.
Simmer until tender: Bring the mixture to a boil, then reduce the heat to low and cover. Simmer for 18 to 20 minutes, or until the rice is tender and the liquid has been absorbed.