Bring a large pot of water to a boil and add salt, garlic powder, and Italian herbs. Cook the pasta until just al dente, following package instructions. Drain and rinse under cold water to stop the cooking process and prevent sticking.
Slice the zucchini, bell pepper, and red onion into grill-friendly pieces. Lightly brush them with oil and sprinkle with salt and pepper. Grill until tender with visible char marks, then remove and let cool slightly before chopping into bite-sized pieces.
In a small bowl, whisk together olive oil, Dijon mustard, lemon juice, dried basil, garlic, salt, and pepper. Add a little water to reach a pourable consistency. The dressing should be smooth and slightly tangy.
In a large bowl, combine cooked pasta, grilled vegetables, chopped tomatoes, chickpeas, and fresh basil. Pour the dressing over everything and toss gently until well coated. Taste and adjust seasoning if needed.
For best results, let the salad chill in the refrigerator for at least 30 minutes. This allows the flavors to blend beautifully. Serve cold or at room temperature for maximum freshness