Mix onion, salt, chili powder, cornstarch, cumin, red pepper flakes, cayenne pepper, garlic, and oregano in a bowl.
Take a large skillet and heat it over a medium-high flame. Add ground beef to it and cook until it turns brown. This may take 7-10 minutes. Drain the excess grease from the skillet.
Place the skillet pack on heat. Add water and seasoning mixture to the beef. Mix them well over medium flame. Cook till all the moisture gets absorbed in the meat. This will take 5 minutes.