Place steaks and marinade in glass baking dish, cover with plastic wrap and place in fridge for 12 to 24 hours. Turn steaks every 4 hours.
To make chipotle sour cream, mince/puree chipotle peppers into sour cream. Let stand for a few minutes and taste. Add additional chipotle peppers for a spicier chipotle sour cream. Chipotle sour cream can be made one day ahead of time. Store in fridge.
About 45 minutes before grilling, remove steaks from fridge and bring to room temperature.
Preheat grill to medium-high heat.
Cook steaks on grill until they reach internal temperature of 135°F for medium-rare doneness. Remove steaks from grill and let stand 5 minutes before slicing.
Slice steaks thin across grain and place on serving platter.