Preheat your grill to medium high. 

Drizzle corn with olive oil and season with salt. Use your hands to thoroughly rub it all over the corn making sure every part of the cob is covered.

Transfer to the grill.

Cook for 7-10 minutes continuing to rotate until the corn is cooked thru and has developed a nice char. Remove from the grill. 

Mix creme Fraiche with lime juice until combined.

Drizzle creme fraiche over the corn. Top with cotija, cilantro, and Tajin to taste.