Put the olive oil into a sauté pan over medium heat. Once hot, add the onion and garlic. Stir until soft and fragrant, about 3 to 5 minutes.
Add the ground beef and break apart with a wooden spoon once it is added to the pan. Stir in the salt, chili powder, oregano and cayenne and continue cooking until cooked through.
Add the tomatoes, ketchup and water. Bring mixture to a boil and then reduce the heat to a simmer. Simmer, stirring occasionally, for about 3 hours. If chili appears to be too dry, add water to desired consistency. Taste and adjust seasoning accordingly.