Peel the corn so that one single layer of husk is remaining. Soak the corn in water for 10 minutes.
While the corn is soaking, heat the grill.
Place the corn on the grill. Cook the corn, turning every 4-5 minutes, until it is charred on all sides.
Let the corn cool until it is able to be handled then peel the remaining husk and cut off the stem of the corn to make a flat base. Stand the corn upright on the flat base and use a large chef's knife to slice off the kernels.
Add the corn kernels, cucumber, radishes, and optional jalapeno into a large bowl
Add the fresh herbs, lime juice, olive oil, salt, and pepper. Mix together and serve.
Notes
Alternate Ideas:
Minced sweet bell pepper works nicely instead of the jalapeños or radishes.
Try it with tomatoes, avocados, and nectarine (with the corn, of course), using the same fresh herbs.
Feta or goat cheese are other delicious topping options.