Step 1
Heat a large skillet over medium heat. Add pine nuts and cook stirring occasionally until toasted and fragrant about 3 minutes. Transfer to a food processor.
Step 2
Place basil leaves 3/4 cup Parmesan cheese 1/2 cup olive oil and 4 cloves garlic in the food processor with the pine nuts. Blend pesto into a smooth paste about 3 minutes.
Step 3
Bring a large pot of lightly salted water to a boil. Cook lasagna noodles in the boiling water stirring occasionally until tender yet firm to the bite about 8 minutes. Drain.
Step 4
Preheat oven to 350 degrees F (175 degrees C). Spray a 9x13-inch casserole dish with cooking spray.
Step 5
Heat 3 tablespoons oil in a large skillet over medium-high heat. Add onion and 3 cloves garlic; cook and stir until translucent about 5 minutes. Add spinach; cook and stir until heated through about 5 minutes. Stir in chicken; cook until heated through about 5 minutes. Season with salt and black pepper.
Step 6
Mix ricotta cheese 3/4 cup Parmesan cheese and egg together in a large bowl. Stir in 1 1/2 cup pesto. Add spinach and chicken mixture; stir to combine.
Step 7
Spread remaining 1/2 cup pesto in the casserole dish. Arrange 4 lasagna noodles slightly overlapping in the bottom of the dish. Top with 1/3 of the ricotta spinach mixture and 1/3 of the mozzarella cheese. Repeat layers twice ending with mozzarella cheese.
Step 8
Bake in the preheated oven until bubbly and golden 35 to 40 minutes.