Preheat your oven to 375°F. Grease a 9x13 baking dish.
Cook the lasagna noodles according to package directions. Drain and set aside.
In a large bowl, mix the shredded chicken with ranch seasoning, cream cheese, sour cream, and milk. Stir until smooth.
Layer 3 lasagna noodles in the prepared baking dish.
Spread a third of the chicken mixture over the noodles. Sprinkle with mozzarella and cheddar.
Repeat the layers two more times, ending with cheese on top.
Cover with foil and bake for 25 minutes. Remove foil and bake another 10-15 minutes until golden and bubbly.
Let it sit for 10 minutes before slicing. Garnish with chopped green onions if you like.