3/4 cup chicken or vegetable stock
In a medium saucepan, heat beans and stock on medium heat until warmed through, about 5 minutes. Remove from heat and stir in shredded Monterey Jack. Cool slightly.
Place the warm bean mixture in a food processor or blender. Puree to a smooth consistency, adding a little more stock or water if needed.
Pour the warm bean mixture back into the saucepan or into a bowl and stir in sour cream, feta, lemon juice, oregano, salt and cayenne pepper.
Transfer to a serving dish. Drizzle with olive oil if desired. Serve warm or at room temperature with chips and vegetables.