To make the filling, heat the olive oil in a medium sauté pan over medium-high heat. Add the onion and garlic and sauté, stirring frequently, until tender, 3 to 4 minutes.
Stir in the cumin and oregano and cook for 30 seconds more. Add the beans and season with the salt and pepper.
Purée the bean mixture with the water. If the beans are too stiff to p