How do I prevent the chicken from drying out?
Use boneless, skinless breasts of similar thickness, butterfly them gently to avoid tearing, and bake at 375°F uncovered only until the internal temperature reaches 165°F (about 25–30 minutes). Ovens vary; check at 20 minutes.
Can I make this ahead of time?
Yes. Stuff and refrigerate the chicken up to 8 hours before baking. Add 5–10 minutes to the baking time if cooking from cold.
What can I substitute for cream cheese?
Use ricotta (slightly less creamy), mascarpone (richer), or a mix of Greek yogurt and softened cream cheese (lighter). Avoid cream cheese substitutes as they may separate.
How do I know when the chicken is done?
Pierce the thickest part of the breast with a meat thermometer; it should read 165°F. The chicken will no longer be pink inside.
Can I use frozen spinach instead of fresh?
Yes. Thaw and squeeze out all excess liquid before chopping, or the filling will be watery.