This soup is super easy to throw together and is guaranteed to be a crowd-pleaser.
Whisk everything but the chicken, cream cheese, milk, and orzo pasta together in a 6-quart slow cooker. Add chicken. Cover and cook on low for 6-8 hours (could be 4-6 depending on slow cooker). When the chicken is cooked through and easily falls apart, remove and shred.
Place shredded chicken back in the slow cooker. Stir in uncooked orzo noodles, cream cheese, milk, and remaining pesto, then cook for another 15-20 minutes or until pasta is cooked.
Once the pasta is cooked, serve or turn the slow cooker to a warm setting—season with kosher salt and pepper.
Top with freshly grated Parmesan cheese, fresh basil, fresh diced tomatoes, or diced red bell pepper.