Preheat grill to medium high. Add the corn to a baking sheet.
Drizzle with melted butter, sprinkle with salt.
Grill over medium high heat until grill marks appear on all sides.
In a blender add the sour cream, chipotle chilies (1 for lower heat, 2 for more heat), and IPA beer, blend until smooth. Add additional beer for thinner sauce.
Add the corn to a serving tray, drizzle with sauce, sprinkle liberally with cotija and cilantro. (roll corn to coat in sauce, if desired).