Chicken Spinach Alfredo Lasagna is a decadent, delicious, and cheesy one pan meal that's sure to become a new favorite at dinner!
Set a skillet over medium heat and add the olive oil. Once the olive oil is hot add the sliced mushrooms. Cook 5 minutes, stirring occasionally.
Add the garlic and spinach to the skillet. Cook 5 more minutes, stirring occasionally. Season with kosher salt, pepper, and crushed red pepper flakes.
Note: You may need to add the spinach in smaller batches and wait until it cooks down. Spinach will get much smaller as it cooks.
Add a few spoonfuls of the alfredo sauce to a 9x13 casserole dish and spread evenly. Lay 4 lasagna sheets flat, overlapping slightly.
Mix together the ricotta cheese and pesto. Spread 1/3 of this mixture over the lasagna sheets.
Evenly spread 1 cup of the cooked, shredded chicken, 1/3 of the spinach and mushroom mixture, 1/4 of the cheese, and 1/4 of the alfredo sauce. Repeat until you have three layers of lasagna.
Top the lasagna with the 4 remaining lasagna sheets, evenly spread the remaining alfredo sauce over top.
Bake in a 375 degree oven for 30 minutes. Top with the remaining mozzarella cheese and bake 15 more minutes.
Sprinkle with fresh parsley if desired.