In a large pot or tub, soak the ears of corn in water at least 30 minutes. Place something heavy on top of them so that they don't float.
Pull the husks back from the corn, remove the corn silk and pull the husks back in place. See notes.
Place the corn directly on a heated grill rack and close the lid.
Turn the corn every 3 minutes and cook about 30 minutes total.
Transfer corn to a platter and without detaching the husks, peel them back completely, turning them inside out so they form a handle.
Brush the corn with some butter and return the corn to the grill for about 5 minutes, turning it frequently.
Return to the platter and brush with the Cilantro Lime Ranch & sprinkle with Tajin or Chili Powder.
Make the Cilantro Lime Ranch
Combine all ingredients in a bowl and mix well. Store in refrigerator until ready to use.
Don't remove the husks before grilling as they are vital to the flavor and cooking process.You can leave the silk on the corn and remove it after it has been grilled. Choice is yours :)The corn is cooked thru when the kernels are easy pierced with a fork.Make sure not to cook it for much longer than 30 minutes on the grill or it will become mushy. Grilled corn will stay warm for about 30 minutes with the husks on. If you need to reheat it for any reason, just place in a microwave covered for about 1.5 minutes to steam it a little bit.