Begin by preparing the shredded chicken. You can use leftover chicken, rotisserie chicken, or cook chicken breasts in a slow cooker with a bit of chicken broth until tender (about 4 hours on low). Once cooked, shred the chicken and set aside.
In a large mixing bowl, combine the shredded chicken, softened cream cheese, ranch seasoning mix, mozzarella cheese, cheddar cheese, garlic powder, and black pepper. Mix until all ingredients are well incorporated.
Preheat your oven to 375°F (190°C).
Spread a thin layer of the chicken mixture on the bottom of the 9x13 inch baking dish.
Place 4 lasagna noodles on top of the mixture, side by side.
Spread half of the ricotta cheese over the noodles, followed by half of the remaining chicken mixture. Repeat this layering process: 4 noodles, the other half of the ricotta, and the other half of the chicken mixture.
Top with the remaining noodles and sprinkle the grated Parmesan cheese over the top.
Cover the baking dish with aluminum foil (avoid direct contact with the cheese) and bake in the preheated oven for 25 minutes.
Remove the foil and bake for an additional 20 minutes, or until the lasagna is bubbly and golden brown on top.
Once done, remove from the oven and let it sit for about 10 minutes before serving. Garnish with chopped green onions for added flavor and freshness.