Bring a large pot of salted water to a boil. Add rotini pasta and cook according to package instructions, about 8-10 minutes until al dente. Drain and rinse with cold water.

Shred or dice the cooked chicken breast. If using leftover chicken, warm gently in the microwave for about 30 seconds.

In a food processor, combine fresh basil leaves, pine nuts, Parmesan cheese, and olive oil. Blend until smooth and seasoned with salt and pepper.

In a large bowl, mix the cooked pasta, shredded chicken, and halved cherry tomatoes. Add the pesto and toss until coated.

Drizzle fresh lemon juice over the salad, stirring gently. Add salt and pepper to enhance flavors.

Transfer the salad to a serving bowl. Serve immediately or chill for 10-15 minutes before serving.