Pesto can be homemade or store-bought; drain excess oil if too oily to avoid greasy bake., Leftovers keep in the refrigerator up to 2 days; reheat gently in oven or skillet to retain juiciness., Dish tastes even better the next day after flavors have mingled overnight., Chicken breasts can be substituted with boneless thighs for juicier meat., Vegetarian alternatives: sliced eggplant or thick tofu slabs, adjusting baking time accordingly., Adding baby spinach or zucchini ribbons under the chicken is a good way to add veggies., Resting the dish after baking helps the cheese set and prevents it from sliding off., Do not pile on too much pesto or it can get greasy unless preferred., Use thicker chicken pieces to avoid overcooking and drying out.