Preheat oven to 375 F.
Spread ½ cup alfredo sauce on the bottom of an 8x8" baking dish and add half the ravioli (12-16, depending on size) in an even layer.
Top with chicken, half the spinach, another ½ cup sauce.
Repeat layers (remaining half ravioli, 1 cup chicken, spinach, ½ cup sauce).
Top with parmesan + mozzarella cheese and bake for 20-30 minutes, or until brown and bubbly.
