Place the corn on a baking sheet and roast in the oven for 25 minutes. When cool enough to handle, scrape the kernels from the cobs.
In a saucepan, melt the butter and add the corn. Stir in the mayonnaise, flour, milk, and cream. Simmer for 2 minutes. Stir in the Jack cheese and simmer for 3-4 minutes until it is completely melted. Stir in the Hatch Chile powders.
Arrange the chips on a platter and top with the dip. Sprinkle with the cilantro and cotija cheese. Mix together the sour cream and heavy cream and drizzle over the top. Serve with the lime wedges.