01 -  Bring a large pot of salted water to a boil. Add pasta and cook until al dente according to package instructions. Reserve 1/2 cup pasta water, drain pasta, and set aside. 
 02 -  While pasta cooks, season chicken pieces with salt and pepper to ensure even flavor distribution. 
 03 -  Heat olive oil in a large skillet over medium-high heat. Add chicken and cook for 5 to 6 minutes, turning occasionally, until golden brown and fully cooked. Transfer chicken to a plate and set aside. 
 04 -  Reduce skillet heat to medium. Add unsalted butter and minced garlic to the pan, stirring for 1 minute until aromatic. 
 05 -  Pour in heavy cream and bring to a gentle simmer. Mix in basil pesto and Parmesan cheese, stirring continuously for 2 to 3 minutes until sauce thickens slightly. 
 06 -  Return the sautéed chicken to the pan and add drained pasta. Toss gently to coat with sauce. Gradually stir in reserved pasta water as needed to reach preferred sauce consistency. 
 07 -  Taste sauce and adjust with additional salt, black pepper, and crushed red pepper flakes if desired. 
 08 -  Serve promptly, garnished with extra grated Parmesan cheese and fresh basil leaves.