Preheat the oven to 400 degrees and carefully slice kernels off the corn. Keep kernels from the 6th ear of corn aside in a separate bowl.
Saute 1 chopped medium onion in 1 tbsp olive oil and 1 tbsp melted butter over medium heat until onions become soft.
Add kernels from 5 ears of corn, a few pinches of sea salt, and freshly ground black pepper. Pour in about 2 cups of chicken broth until corn and onions are covered. Bring to a boil.
Lower to a simmer, cover the pot, and cook for 15-20 minutes.
Meanwhile, toss the remaining kernels from the 6th ear of corn with 1 tbsp olive oil and a pinch of sea salt. Lay the corn you tossed on a baking sheet lined with parchment paper.
Bake corn in preheated 400 degree oven for about 15 minutes, until golden. Let cool.
Remove corn from soup pot with a slotted spoon and puree in a blender (careful! do not put top on blender, just use a dishtowel as the heat will make it explode!!). Pour pureed corn back into pot with any remaining broth.
Serve topped with roasted corn kernels and a squeeze of fresh lime juice (optional). Enjoy!