Preheat and prep: Heat the oven to 400°F (200°C).
Lightly grease a 9x13-inch baking dish with olive oil or cooking spray.
Season the chicken: Pat the chicken dry, then rub with olive oil. Sprinkle evenly with salt, pepper, garlic powder, and onion powder. Arrange in a single layer in the baking dish.
Make the topping: In a large bowl, combine Greek yogurt, cream cheese, and mayonnaise until smooth.
Stir in 1/2 cup Parmesan, mozzarella, garlic, lemon zest, lemon juice, and red pepper flakes (if using).
Add the greens: Fold in chopped spinach and chopped artichoke hearts. If using frozen spinach, make sure it’s fully thawed and squeezed dry to avoid excess water.
Top the chicken: Spread the spinach-artichoke mixture evenly over each chicken breast. Sprinkle the remaining 1/4 cup Parmesan over the top.
Bake: Place the dish on the center rack and bake for 22–28 minutes, or until the chicken reaches an internal temperature of 165°F (74°C).
Thicker breasts may need a few more minutes.
Broil for color (optional): For a golden top, broil on high for 1–2 minutes at the end. Watch closely to prevent burning.
Rest and serve: Let the bake rest for 5 minutes before serving. Spoon any creamy juices from the pan over the chicken.