Prepare the Marinade: In a mixing bowl, whisk together olive oil, vinegar, Italian seasoning, garlic powder, salt, and pepper until well combined.
Marinate the Cheese: Add the cheddar and pepper jack cheese cubes to the marinade. Toss gently to ensure each piece is thoroughly coated. Cover the bowl and let the mixture marinate in the refrigerator for at least 30 minutes, allowing the flavors to meld.
Assemble the Appetizer: On a serving platter, arrange the marinated cheese cubes. Distribute the salami pieces and sliced pickles around the cheese to create an appealing presentation.
Garnish and Serve: Sprinkle fresh herbs over the assembled appetizer for a burst of color and added flavor. Serve immediately, either on its own or accompanied by an assortment of crackers or crusty bread.