Roasting a poblano pepper: preheat your oven to 450 degrees F (230 C).

Cut your poblano pepper down the center into two halves and remove the stem and all the seeds. 

Place your pepper halves face down on an aluminum foil-lined sheet pan. 

Bake for 20 to 25 minutes or until the skin of the pepper is turning fairly black. 

Remove your pepper halves from the oven and transfer into a bowl large enough to hold them. At this point you want to steam them slightly to make the skins easier to remove. You can either cover your bowl with another inverted bowl or you can cover your bowl with something like plastic wrap. Covering a bowl with a cutting board will also work. You're just trying to trap the stem in with the roasted pepper halves. 

After about 5 or 10 minutes, your pepper should be cool enough to handle. 

Remove from the bowl to a cutting board and carefully strip off all the skins and the burned or charred bits of pepper skin or flesh. Discard all the burned parts and the skin. 

Slice your roasted peppers into slices and then slice the slices into a small dice. Place the diced poblano in a large bowl.

Cooking corn kernels: clean eight ears of corn and slice the kernels from the cob. Add a teaspoon of olive oil to a large pan over medium heat and when the oil is shimmering, add the corn kernels. Cook, stirring often until the corn is just starting to soften and brown in some spots. This should take about 10 or 15 minutes. 

Add the cooked corn kernels to the large bowl with the diced poblano to cool.

Corn salsa assembly: finely dice half of a large red onion and a jalapeno pepper and add them both to the bowl with the corn and poblano. 

Add lime juice, cilantro, cumin, and salt to the bowl with the corn and all other veggies. Stir together well and then store in a sealed container in the fridge for up to a week.