In a large pot, bring salted water to a rolling boil over high heat. Add your rotini pasta and cook according to the package instructions, typically around 8–10 minutes, until it's al dente. Stir occasionally to prevent sticking.

Once the pasta is cooked, carefully drain it using a colander and rinse under cold water to stop the cooking process. Spread it out on a baking sheet to cool completely.

In a large mixing bowl, combine the cooled rotini pasta with diced chicken, halved cherry tomatoes, diced cucumber, thinly sliced red onion, crumbled feta cheese, and chopped fresh basil. Gently stir everything together.

In a small bowl, whisk together olive oil, balsamic vinegar, Dijon mustard, honey, and a pinch of salt and pepper until fully combined.

Drizzle the prepared balsamic vinaigrette over the pasta salad mixture. Toss everything together until all ingredients are well-coated. Cover with plastic wrap or a lid and refrigerate for at least 30 minutes.

After chilling, give the salad a gentle toss to refresh the flavors. Serve your Grilled Chicken Pasta Salad with Balsamic Vinaigrette chilled or at room temperature.