Place the poblano pepper directly on the stove over medium heat (this needs to be done with a gas stove top). Turn and cook until all sides of the poblano have blackened. Once completely roasted, transfer onto aluminum foil and cover. Let rest for 10 minutes.

Once the poblano has cooled, dice up and place in a medium bowl.

Heat a skillet over medium-high heat with butter. Add the corn and shallots. Cook and stir for 10 to 15 minutes, until the corn has started to brown. Transfer to the bowl with the diced poblano and allow to cool.

Add the avocado, cilantro, grapefruit juice, and lime juice. Mix until just combined. Taste and season with salt and pepper. Top with flaky sea salt before serving with tortilla chips.