Bring a large pot of salted water to a boil. Add rotini pasta and cook for 8-10 minutes until al dente. Drain and rinse under cold water. Set aside in a mixing bowl.

Dice avocado and halve cherry tomatoes. Chop red onion and tear basil leaves. Set aside.

Add shredded chicken to the bowl with cooked pasta and mix.

In a jar, combine olive oil, white wine vinegar, Italian seasoning, salt, and pepper. Shake until emulsified.

Drizzle dressing over the pasta and chicken. Fold in avocado, tomatoes, onion, and basil gently.

Serve immediately or refrigerate for up to 3 days, adding avocado just before serving.