Have ready the chicken stock in a small sauce pan over low heat.
Start a fire in the grill and allow it to burn to medium temperature. Carefully peel back the husks of each ear of corn, ensuring that the husks remain attached at the base, and remove the silks. In a small saucepan, over low heat, melt the butter. Add the garlic, thyme, rosemary, 1/4 t kosher salt and 1/4 t of the white pepper to the butter and stir well. Brush the herb butter over the corn. Close the husks over the corn and tie with butcher's string to hold in place. Place the corn on the grill and cook, turning to cook on all sides, about 15 minutes. The husks and a few kernels will char and blacken, but the corn will be cooked properly inside the husks. Remove from the grill and allow to cool. Remove and discard the husks. Using a small sharp knife, cut a slit down the middle of each row of corn kernels. Then, holding the corn by the stalk, using the same knife held perpendicular to the corn, scrape down the ear, removing the creamy inside of the kernels. Repeat the procedure with each ear of corn. Transfer the scrapings to a medium saucepan. Add the stock and cream. Over medium heat, warm the creamed corn through, about 5 to 10 minutes. Correct the seasoning to taste with kosher salt and white pepper. Serve immediately or keep warm in a double boiler until needed.