Roast the Poblano Pepper: If you have a gas range, hold the poblano pepper over the open flame with tongs. Rotate and blister the pepper on all sides, until it is mostly black. You can also do this on the grill. If you don’t have a gas range or grill, turn the oven on broil, and blister the pepper under the broiler, rotating to all sides as needed.
Once the poblano is roasted and black, place it in a zip bag and seal. Allow the pepper to steam for 15 minutes. Then peel off the waxy skin. Remove the seeds and chop the pepper.
Seed and chop the jalapeno, onion, and cilantro.
Set out a large mixing bowl. Add the thawed corn, chopped poblano, jalapeno, onion, and cilantro. Mix in the lime and lemon juice. Salt and pepper generously. Taste, then add additional salt and pepper if needed.
Serve with tortilla chips, on salads, in burrito bowls, or on pork chops or steaks. You can make ahead and refrigerate up to 5 days in advance.