Heat vegetable oil in a Dutch oven over medium-high heat. Place the beef sirloin in the Dutch oven and cook until the cubes are brown on all sides, about 10 minutes. Reduce the heat to medium and add the onion, red bell pepper, tomatoes, garlic, cumin, oregano, garlic powder, salt, black pepper, paprika, and water.
Continue cooking, stirring often, until the meat is tender, about 30 minutes.
