In a 6 quart pan on medium heat add the olive oil, then add bacon grease and stir add about 1 to ½ cups of chicken broth and stir then add 2 12 cans of beans and stir, turn down heat, meanwhile put 2 ½ cans of beans in food processor add ½ cup of chicken broth and emulsify then add the emulsified beans to the soup mixture and stir. Add the Cayenne pepper and taco sauce heat till boiling. Serve soup with a dollop of Sour Cream.