Preheat the grill to medium-high heat.
In a large mixing bowl, combine the zucchini slices with olive oil, red wine vinegar, dried basil, dried parsley, and garlic powder. Toss well to ensure each piece is evenly coated. Sprinkle with ¼ teaspoon salt and freshly ground black pepper, adjusting the seasoning to taste.
Once the grill is hot, carefully use tongs to rub an oiled paper towel over the grates to clean and prevent sticking.
Using tongs, place the zucchini slices directly on the grill grates in a single layer. Cover and cook for 2 to 3 minutes until grill marks begin to form. Flip each slice and continue grilling, covered, for another 2 to 3 minutes, or until the zucchini is tender but still holds its shape.
Remove from the grill, taste, and adjust seasoning if needed. Serve immediately while warm for the best flavor and texture.