Place the olives and basil in the bowl of a food processor; process until finely chopped. Add the salt and pulse to combine. Spread the salt mixture on a baking sheet; place in the oven for 30 minutes, or until the mixture is quite dry. Remove and let cool, then break apart using your fingers.
Place a large skillet over medium-high heat. Add the grapeseed oil and give it 1 minute to heat up. In batches, so as to not overcrowd the pan, fry the peppers until blistered on all sides, 2 or 3 minutes per side. With tongs or a slotted spoon, remove the peppers to a paper-towel-lined plate and immediately sprinkle with some of the flavored salt; use about 2 tablespoons of the salt mixture and reserve the rest in an airtight container in the refrigerator for a later use.