Roughly chop the green olives, Kalamata olives, pepperoncini, giardiniera, roasted red peppers, capers, cocktail onions, garlic, celery, and carrot until coarsely combined.
1 cup green olives, ½ cup Kalamata olives, ½ cup pepperoncini, 1 cup giardiniera, ½ cup roasted red peppers, 2 tablespoons capers, ¼ cup cocktail onions, 3 cloves garlic, ¼ cup celery
, ¼ cup carrot
Transfer the mixture to a medium nonreactive bowl.
Add oregano, basil, and black pepper.
1 teaspoon dried oregano, 1 teaspoon dried basil, ¾ teaspoon ground black pepper
Pour in olive oil, canola oil, and red wine vinegar.
½ cup olive oil, ¼ cup canola oil, ¼ cup red wine vinegar
Stir until evenly combined.
Transfer to a glass jar or nonreactive container. If needed, add additional olive oil to ensure the mixture is fully submerged.
Cover and refrigerate for at least 8 hours or overnight to allow flavors to develop.