Preheat oven to 350 degrees. Coat a casserole dish with oil.
Cook noodles according to package directions and drain.
Make the Alfredo sauce while the noodles are cooking.
Melt butter in a medium sauce pot. Once the butter is melted add cornstarch. Stir until smooth. Cook over a medium-high flame until the mixture is smooth and bubbly, stirring constantly.
Add milk slowly, stirring until well blended.
Add broth, 2 cups of cheese, garlic powder, parsley and pepper. Stir over a medium flame, until cheese is melted and the sauce is smooth.
Spoon a small amount of sauce on the bottom of a greased 9×12 pan. Place 3 – 4 lasagna noodles on the bottom. Place 1 cup of cut chicken and 2 cups of broccoli on top of the noodles. Spoon 1 – 1 1/2 cups Alfredo sauce over the chicken and broccoli.
Place 3 – 4 lasagna noodles on top of the Alfredo sauce. Place 1 cup of cut chicken and 2 cups of broccoli on top of the noodles. Spoon 1 – 1 1/2 cups Alfredo sauce over the chicken and broccoli.
Place 3 – 4 lasagna noodles on top of the Alfredo sauce. Spread the remaining Alfredo sauce on top of the noodles. Place the remaining chicken and broccoli over the Alfredo sauce. Sprinkle the mozzarella cheese over the broccoli and chicken.
Cover with foil and bake at 350 degrees for 30 minutes. Remove foil and bake for another 5 – 10 minutes until the cheese just starts to brown.
Let stand for 5 minutes before serving.