Add all the ingredients to the work bowl of a food processor and pulse until the ingredients are coarsely chopped and incorporated.
Remove the lid, scrape down the sides. If the relish seems dry, add more olive oil.
Pulse 1-2 more times until the relish is the consistency of pesto.
Taste for seasoning, adding more salt, if needed, and set aside until ready to use. (Or transfer to a jar and refrigerate for the next day. Remove it from the refrigerator and bring to room temperature before serving.)