Adam and I tried as we might to experiment with food.  In Argentina, that means trying new types of meat as the Parrilla (grill) is basically the national food.  We would gorge ourselves nightly at a Tenedor Libre (free fork).  We tried something new every night.  First it was Morcilla (blood sausage), this night it was kidney.  We should have known when the guy working the parrilla recommended against the kidney.  It tasted pretty much how you would expect an organ that filters all the bad stuff out of your body to taste. 

Just in case you are curious and have a kidney or two to grill up, I would not recommend.