Cut tenderloins into 1 inch medallions, flatten slightly.
Combine next four ingredients with medallions in large zipper bag, sealed after squeezing air out. Refrigerate at least 4 hours.
Remove pork from marinade, grill over low-medium heat BBQ 3 – 4 minutes each side, until light in colour.
Whip together ingredients with blender until smooth and creamy.
Top tenderloins with dab of butter before serving.