Bring a large pot of water to a boil. Cook the cheese tortellini according to the package directions. After cooking, drain the tortellini and rinse with cold water to chill it quickly.

In a bowl, whisk together the olive oil, red wine vinegar, Italian seasoning, minced garlic, Dijon mustard, salt, and pepper. Mix until the dressing is well combined and creamy.

In a large bowl, toss together the cooked tortellini, halved grape tomatoes, chopped salami, sliced black olives, diced red onion, and chopped fresh basil. Ensure everything is evenly mixed.

Pour the prepared dressing over the tortellini mixture. Toss gently to combine, ensuring that all ingredients are well coated with the dressing.

Cover the bowl and store the salad in the fridge until you are ready to serve. This allows the flavors to develop further.