Preheat oven to 400 degrees F.
To layer the lasagna, divide the ingredients so that you will have four layers of pasta (with three sheets of pasta per layer). Divide the the sour cream, chicken, black beans, and corn into thirds as there will be three layers in between the pasta layers. Likewise, the sauce and shredded cheese will be divided into four parts (with additional sauce under the first layer of pasta), distributing between the inside layers but also topping the final pasta layer with sauce and then cheese.
Using an 11x17 casserole dish, spread a thin layer of enchilada sauce on the bottom of the dish and cover with three pasta sheets.
Add a layer of sour cream, chicken, black beans, corn, more enchilada sauce, and shredded cheese.
Continue to layer with three sheets of pasta topped with a layer of sour cream, chicken, black beans, corn, more enchilada sauce, and shredded cheese. You final layer will be pasta topped with cheese and sauce.
Cover with aluminum foil and bake in preheated oven for 40-50 minutes until pasta is soft. You may need to remove the foil during the final few minutes of baking to fully melt the cheese.
Top with fresh cilantro and avocado before serving.