Process cooked chicken breasts into 0.5-inch uniform cubes and place in a chilled mixing bowl.
In a separate vessel, whisk together basil pesto, mayonnaise, Greek yogurt, and lemon juice until a homogenous emulsion is formed.
Incorporate the dressing into the chicken cubes using a folding motion to ensure even distribution without breaking the protein structure.
Add halved cherry tomatoes, toasted pine nuts, and Parmesan cheese to the mixture.
Adjust seasoning with kosher salt and ground black pepper to taste.
Transfer to an airtight container and refrigerate at 40°F (4°C) for a minimum of 30 minutes to facilitate flavor maturation before service.