Boil the potatoes in salted water until tender, about 12 to 15 minutes.
While the potatoes cook, whisk together olive oil, red wine vinegar, garlic, mustard, Italian seasoning, pepper, and salt in a large bowl.
Drain the potatoes and add them to the dressing while still hot. Toss to coat and let cool for 20 minutes.
Add the onion, artichokes, mozzarella, olives, tomatoes, soppressata, basil, and parsley. Gently toss until everything is well combined. Enjoy your vibrant, flavorful potato salad!