Preheat your oven to 375°F (190°C).
In a large pot of boiling salted water, cook the lasagna noodles according to package instructions until al dente. Drain and set aside.
In a skillet over medium heat, add the olive oil. Once hot, add the sliced mushrooms and chopped spinach. Season with garlic powder, Italian seasoning, salt, and pepper. Sauté until the mushrooms are tender and the spinach is wilted, about 5 minutes. Remove from heat.
In a large mixing bowl, combine the ricotta cheese, half of the mozzarella cheese, and half of the Parmesan cheese. Add the shredded chicken and the sautéed vegetables. Mix until well combined.
Spread a thin layer of Alfredo sauce on the bottom of your baking dish. Place 3 lasagna noodles on top. Layer half of the chicken and cheese mixture over the noodles, followed by a third of the remaining Alfredo sauce. Repeat the layers, finishing with the last 3 noodles on top. Spread the remaining Alfredo sauce over the top and sprinkle with the remaining mozzarella and Parmesan cheese.
Cover the baking dish with aluminum foil and bake in the preheated oven for 25 minutes. Remove the foil and bake for an additional 15-20 minutes, or until the cheese is bubbly and golden brown.
Once out of the oven, allow the Loaded Chicken Alfredo Lasagna to cool for about 10 minutes. Serve warm and enjoy!