In a Dutch oven, heat the olive oil over medium-high heat. Add the beef and cook for 7 minutes. Add the onion, garlic, chili powder and cumin and cook over medium-low heat for 5 minutes. Add the beans, with their liquid, and the tomatoes; bring to a simmer. Cook, stirring occasionally, until thick, about 15 minutes. Season with salt and pepper.
Stir in the cilantro, then top with the cheese, cover and let stand until the cheese melts, 5 to 10 minutes. Place a handful of corn chips in each of 4 bowls. Top with the chili and serve.
